diff --git a/include/mqtt_client.h b/include/mqtt_client.h
index 37f416a..c90b2f7 100644
--- a/include/mqtt_client.h
+++ b/include/mqtt_client.h
@@ -165,7 +165,7 @@ typedef struct {
     void *user_context;                     /*!< pass user context to this option, then can receive that context in ``event->user_context`` */
     int task_prio;                          /*!< MQTT task priority, default is 5, can be changed in ``make menuconfig`` */
     int task_stack;                         /*!< MQTT task stack size, default is 6144 bytes, can be changed in ``make menuconfig`` */
-    int buffer_size;                        /*!< size of MQTT send/receive buffer, default is 1024 */
+    int buffer_size;                        /*!< size of MQTT send/receive buffer, default is 1024 (only receive buffer size if ``out_buffer_size`` defined) */
     const char *cert_pem;                   /*!< Pointer to certificate data in PEM or DER format for server verify (with SSL), default is NULL, not required to verify the server. PEM-format must have a terminating NULL-character. DER-format requires the length to be passed in cert_len. */
     size_t cert_len;                        /*!< Length of the buffer pointed to by cert_pem. May be 0 for null-terminated pem */
     const char *client_cert_pem;            /*!< Pointer to certificate data in PEM or DER format for SSL mutual authentication, default is NULL, not required if mutual authentication is not needed. If it is not NULL, also `client_key_pem` has to be provided. PEM-format must have a terminating NULL-character. DER-format requires the length to be passed in client_cert_len. */
@@ -181,6 +181,7 @@ typedef struct {
     const char *clientkey_password;         /*!< Client key decryption password string */
     int clientkey_password_len;             /*!< String length of the password pointed to by clientkey_password */
     esp_mqtt_protocol_ver_t protocol_ver;   /*!< MQTT protocol version used for connection, defaults to value from menuconfig*/
+    int out_buffer_size;                    /*!< size of MQTT output buffer. If not defined, both output and input buffers have the same size defined as ``buffer_size`` */
 } esp_mqtt_client_config_t;
 
 /**
diff --git a/mqtt_client.c b/mqtt_client.c
index 3ee2028..9372512 100644
--- a/mqtt_client.c
+++ b/mqtt_client.c
@@ -654,14 +654,16 @@ esp_mqtt_client_handle_t esp_mqtt_client_init(const esp_mqtt_client_config_t *co
     if (buffer_size <= 0) {
         buffer_size = MQTT_BUFFER_SIZE_BYTE;
     }
+    // use separate value for output buffer size if configured
+    int out_buffer_size = config->out_buffer_size > 0 ? config->out_buffer_size : buffer_size;
 
     client->mqtt_state.in_buffer = (uint8_t *)malloc(buffer_size);
     ESP_MEM_CHECK(TAG, client->mqtt_state.in_buffer, goto _mqtt_init_failed);
     client->mqtt_state.in_buffer_length = buffer_size;
-    client->mqtt_state.out_buffer = (uint8_t *)malloc(buffer_size);
+    client->mqtt_state.out_buffer = (uint8_t *)malloc(out_buffer_size);
     ESP_MEM_CHECK(TAG, client->mqtt_state.out_buffer, goto _mqtt_init_failed);
 
-    client->mqtt_state.out_buffer_length = buffer_size;
+    client->mqtt_state.out_buffer_length = out_buffer_size;
     client->mqtt_state.connect_info = &client->connect_info;
     client->outbox = outbox_init();
     ESP_MEM_CHECK(TAG, client->outbox, goto _mqtt_init_failed);