diff --git a/components/esp_eth/CMakeLists.txt b/components/esp_eth/CMakeLists.txt
index 21b64cc7a9..90e69186ad 100644
--- a/components/esp_eth/CMakeLists.txt
+++ b/components/esp_eth/CMakeLists.txt
@@ -6,7 +6,7 @@ set(priv_requires)
 
 # If Ethernet disabled in Kconfig, this is a config-only component
 if(CONFIG_ETH_ENABLED)
-    set(srcs "src/esp_eth.c")
+    set(srcs "src/esp_eth.c" "src/esp_eth_phy.c")
     set(include "include")
     set(priv_requires "driver" "log") # require "driver" for using some GPIO APIs
 
diff --git a/components/esp_eth/include/esp_eth_com.h b/components/esp_eth/include/esp_eth_com.h
index 2f40c645b7..ad7aa185f8 100644
--- a/components/esp_eth/include/esp_eth_com.h
+++ b/components/esp_eth/include/esp_eth_com.h
@@ -206,6 +206,19 @@ typedef enum {
 */
 ESP_EVENT_DECLARE_BASE(ETH_EVENT);
 
+/**
+* @brief Detect PHY address
+*
+* @param[in] eth: mediator of Ethernet driver
+* @param[out] detected_addr: a valid address after detection
+* @return
+*       - ESP_OK: detect phy address successfully
+*       - ESP_ERR_INVALID_ARG: invalid parameter
+*       - ESP_ERR_NOT_FOUND: can't detect any PHY device
+*       - ESP_FAIL: detect phy address failed because some error occurred
+*/
+esp_err_t esp_eth_detect_phy_addr(esp_eth_mediator_t *eth, uint32_t *detected_addr);
+
 #ifdef __cplusplus
 }
 #endif
diff --git a/components/esp_eth/include/esp_eth_phy.h b/components/esp_eth/include/esp_eth_phy.h
index 2e27350e3a..4aedff1112 100644
--- a/components/esp_eth/include/esp_eth_phy.h
+++ b/components/esp_eth/include/esp_eth_phy.h
@@ -21,6 +21,8 @@ extern "C" {
 #include "esp_eth_com.h"
 #include "sdkconfig.h"
 
+#define ESP_ETH_PHY_ADDR_AUTO (-1)
+
 /**
 * @brief Ethernet PHY
 *
@@ -176,7 +178,7 @@ struct esp_eth_phy_s {
 *
 */
 typedef struct {
-    uint32_t phy_addr;            /*!< PHY address */
+    int32_t phy_addr;             /*!< PHY address, set -1 to enable PHY address detection at initialization stage */
     uint32_t reset_timeout_ms;    /*!< Reset timeout value (Unit: ms) */
     uint32_t autonego_timeout_ms; /*!< Auto-negotiation timeout value (Unit: ms) */
     int reset_gpio_num;           /*!< Reset GPIO number, -1 means no hardware reset */
@@ -186,12 +188,12 @@ typedef struct {
  * @brief Default configuration for Ethernet PHY object
  *
  */
-#define ETH_PHY_DEFAULT_CONFIG()     \
-    {                                \
-        .phy_addr = 1,               \
-        .reset_timeout_ms = 100,     \
-        .autonego_timeout_ms = 4000, \
-        .reset_gpio_num = 5,         \
+#define ETH_PHY_DEFAULT_CONFIG()           \
+    {                                      \
+        .phy_addr = ESP_ETH_PHY_ADDR_AUTO, \
+        .reset_timeout_ms = 100,           \
+        .autonego_timeout_ms = 4000,       \
+        .reset_gpio_num = 5,               \
     }
 
 /**
diff --git a/components/esp_eth/src/esp_eth_phy.c b/components/esp_eth/src/esp_eth_phy.c
new file mode 100644
index 0000000000..d77812f907
--- /dev/null
+++ b/components/esp_eth/src/esp_eth_phy.c
@@ -0,0 +1,44 @@
+// Copyright 2019 Espressif Systems (Shanghai) PTE LTD
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+#include <string.h>
+#include <stdlib.h>
+#include "esp_log.h"
+#include "esp_eth.h"
+#include "eth_phy_regs_struct.h"
+
+static const char *TAG = "esp_eth.phy";
+
+esp_err_t esp_eth_detect_phy_addr(esp_eth_mediator_t *eth, uint32_t *detected_addr)
+{
+    if (!eth || !detected_addr) {
+        ESP_LOGE(TAG, "eth and detected_addr can't be null");
+        return ESP_ERR_INVALID_ARG;
+    }
+    uint32_t addr_try = 0;
+    uint32_t reg_value = 0;
+    for (; addr_try < 16; addr_try++) {
+        eth->phy_reg_read(eth, addr_try, ETH_PHY_IDR1_REG_ADDR, &reg_value);
+        if (reg_value != 0xFFFF && reg_value != 0x00) {
+            *detected_addr = addr_try;
+            break;
+        }
+    }
+    if (addr_try < 16) {
+        ESP_LOGD(TAG, "Found PHY address: %d", addr_try);
+        return ESP_OK;
+    } else {
+        ESP_LOGE(TAG, "No PHY device detected");
+        return ESP_ERR_NOT_FOUND;
+    }
+}
diff --git a/components/esp_eth/src/esp_eth_phy_dm9051.c b/components/esp_eth/src/esp_eth_phy_dm9051.c
index c3775f2042..286a7baa56 100644
--- a/components/esp_eth/src/esp_eth_phy_dm9051.c
+++ b/components/esp_eth/src/esp_eth_phy_dm9051.c
@@ -285,6 +285,10 @@ static esp_err_t dm9051_init(esp_eth_phy_t *phy)
 {
     phy_dm9051_t *dm9051 = __containerof(phy, phy_dm9051_t, parent);
     esp_eth_mediator_t *eth = dm9051->eth;
+    // Detect PHY address
+    if (dm9051->addr == ESP_ETH_PHY_ADDR_AUTO) {
+        PHY_CHECK(esp_eth_detect_phy_addr(eth, &dm9051->addr) == ESP_OK, "Detect PHY address failed", err);
+    }
     /* Power on Ethernet PHY */
     PHY_CHECK(dm9051_pwrctl(phy, true) == ESP_OK, "power control failed", err);
     /* Reset Ethernet PHY */
@@ -315,7 +319,6 @@ err:
 esp_eth_phy_t *esp_eth_phy_new_dm9051(const eth_phy_config_t *config)
 {
     PHY_CHECK(config, "can't set phy config to null", err);
-    PHY_CHECK(config->phy_addr == 1, "dm9051's phy address can only set to 1", err);
     phy_dm9051_t *dm9051 = calloc(1, sizeof(phy_dm9051_t));
     PHY_CHECK(dm9051, "calloc dm9051 failed", err);
     dm9051->addr = config->phy_addr;
diff --git a/components/esp_eth/src/esp_eth_phy_dp83848.c b/components/esp_eth/src/esp_eth_phy_dp83848.c
index fbb41391a9..9bcfeeda18 100644
--- a/components/esp_eth/src/esp_eth_phy_dp83848.c
+++ b/components/esp_eth/src/esp_eth_phy_dp83848.c
@@ -41,7 +41,7 @@ static const char *TAG = "dp83848";
 typedef union {
     struct {
         uint32_t link_status : 1;               /* Link Status */
-        uint32_t speed_status : 1;              /* Link Status */
+        uint32_t speed_status : 1;              /* Speed Status */
         uint32_t duplex_status : 1;             /* Duplex Status */
         uint32_t loopback_status : 1;           /* MII Loopback */
         uint32_t auto_nego_complete : 1;        /* Auto-Negotiation Complete */
@@ -98,17 +98,14 @@ static esp_err_t dp83848_update_link_duplex_speed(phy_dp83848_t *dp83848)
     esp_eth_mediator_t *eth = dp83848->eth;
     eth_speed_t speed = ETH_SPEED_10M;
     eth_duplex_t duplex = ETH_DUPLEX_HALF;
-    bmsr_reg_t bmsr;
     physts_reg_t physts;
-    PHY_CHECK(eth->phy_reg_read(eth, dp83848->addr, ETH_PHY_BMSR_REG_ADDR, &(bmsr.val)) == ESP_OK,
-              "read BMSR failed", err);
-    eth_link_t link = bmsr.link_status ? ETH_LINK_UP : ETH_LINK_DOWN;
+    PHY_CHECK(eth->phy_reg_read(eth, dp83848->addr, ETH_PHY_STS_REG_ADDR, &(physts.val)) == ESP_OK,
+              "read PHYSTS failed", err);
+    eth_link_t link = physts.link_status ? ETH_LINK_UP : ETH_LINK_DOWN;
     /* check if link status changed */
     if (dp83848->link_status != link) {
         /* when link up, read negotiation result */
         if (link == ETH_LINK_UP) {
-            PHY_CHECK(eth->phy_reg_read(eth, dp83848->addr, ETH_PHY_STS_REG_ADDR, &(physts.val)) == ESP_OK,
-                      "read PHYSTS failed", err);
             if (physts.speed_status) {
                 speed = ETH_SPEED_10M;
             } else {
@@ -283,6 +280,10 @@ static esp_err_t dp83848_init(esp_eth_phy_t *phy)
 {
     phy_dp83848_t *dp83848 = __containerof(phy, phy_dp83848_t, parent);
     esp_eth_mediator_t *eth = dp83848->eth;
+    // Detect PHY address
+    if (dp83848->addr == ESP_ETH_PHY_ADDR_AUTO) {
+        PHY_CHECK(esp_eth_detect_phy_addr(eth, &dp83848->addr) == ESP_OK, "Detect PHY address failed", err);
+    }
     /* Power on Ethernet PHY */
     PHY_CHECK(dp83848_pwrctl(phy, true) == ESP_OK, "power control failed", err);
     /* Reset Ethernet PHY */
diff --git a/components/esp_eth/src/esp_eth_phy_ip101.c b/components/esp_eth/src/esp_eth_phy_ip101.c
index 6b16c2188a..c3ea8a1b01 100644
--- a/components/esp_eth/src/esp_eth_phy_ip101.c
+++ b/components/esp_eth/src/esp_eth_phy_ip101.c
@@ -128,17 +128,14 @@ static esp_err_t ip101_update_link_duplex_speed(phy_ip101_t *ip101)
     eth_speed_t speed = ETH_SPEED_10M;
     eth_duplex_t duplex = ETH_DUPLEX_HALF;
     cssr_reg_t cssr;
-    bmsr_reg_t bmsr;
     PHY_CHECK(ip101_page_select(ip101, 16) == ESP_OK, "select page 16 failed", err);
-    PHY_CHECK(eth->phy_reg_read(eth, ip101->addr, ETH_PHY_BMSR_REG_ADDR, &(bmsr.val)) == ESP_OK,
-              "read BMSR failed", err);
-    eth_link_t link = bmsr.link_status ? ETH_LINK_UP : ETH_LINK_DOWN;
+    PHY_CHECK(eth->phy_reg_read(eth, ip101->addr, ETH_PHY_CSSR_REG_ADDR, &(cssr.val)) == ESP_OK,
+              "read CSSR failed", err);
+    eth_link_t link = cssr.link_up ? ETH_LINK_UP : ETH_LINK_DOWN;
     /* check if link status changed */
     if (ip101->link_status != link) {
         /* when link up, read negotiation result */
         if (link == ETH_LINK_UP) {
-            PHY_CHECK(eth->phy_reg_read(eth, ip101->addr, ETH_PHY_CSSR_REG_ADDR, &(cssr.val)) == ESP_OK,
-                      "read CSSR failed", err);
             switch (cssr.op_mode) {
             case 1: //10M Half
                 speed = ETH_SPEED_10M;
@@ -320,6 +317,10 @@ static esp_err_t ip101_init(esp_eth_phy_t *phy)
 {
     phy_ip101_t *ip101 = __containerof(phy, phy_ip101_t, parent);
     esp_eth_mediator_t *eth = ip101->eth;
+    // Detect PHY address
+    if (ip101->addr == ESP_ETH_PHY_ADDR_AUTO) {
+        PHY_CHECK(esp_eth_detect_phy_addr(eth, &ip101->addr) == ESP_OK, "Detect PHY address failed", err);
+    }
     /* Power on Ethernet PHY */
     PHY_CHECK(ip101_pwrctl(phy, true) == ESP_OK, "power control failed", err);
     /* Reset Ethernet PHY */
diff --git a/components/esp_eth/src/esp_eth_phy_lan8720.c b/components/esp_eth/src/esp_eth_phy_lan8720.c
index d7d62bb781..b6480a6649 100644
--- a/components/esp_eth/src/esp_eth_phy_lan8720.c
+++ b/components/esp_eth/src/esp_eth_phy_lan8720.c
@@ -364,6 +364,10 @@ static esp_err_t lan8720_init(esp_eth_phy_t *phy)
 {
     phy_lan8720_t *lan8720 = __containerof(phy, phy_lan8720_t, parent);
     esp_eth_mediator_t *eth = lan8720->eth;
+    // Detect PHY address
+    if (lan8720->addr == ESP_ETH_PHY_ADDR_AUTO) {
+        PHY_CHECK(esp_eth_detect_phy_addr(eth, &lan8720->addr) == ESP_OK, "Detect PHY address failed", err);
+    }
     /* Power on Ethernet PHY */
     PHY_CHECK(lan8720_pwrctl(phy, true) == ESP_OK, "power control failed", err);
     /* Reset Ethernet PHY */
diff --git a/components/esp_eth/src/esp_eth_phy_rtl8201.c b/components/esp_eth/src/esp_eth_phy_rtl8201.c
index 814563fdc1..2a5808a22c 100644
--- a/components/esp_eth/src/esp_eth_phy_rtl8201.c
+++ b/components/esp_eth/src/esp_eth_phy_rtl8201.c
@@ -271,6 +271,10 @@ static esp_err_t rtl8201_init(esp_eth_phy_t *phy)
 {
     phy_rtl8201_t *rtl8201 = __containerof(phy, phy_rtl8201_t, parent);
     esp_eth_mediator_t *eth = rtl8201->eth;
+    // Detect PHY address
+    if (rtl8201->addr == ESP_ETH_PHY_ADDR_AUTO) {
+        PHY_CHECK(esp_eth_detect_phy_addr(eth, &rtl8201->addr) == ESP_OK, "Detect PHY address failed", err);
+    }
     /* Power on Ethernet PHY */
     PHY_CHECK(rtl8201_pwrctl(phy, true) == ESP_OK, "power control failed", err);
     /* Reset Ethernet PHY */