diff --git a/esphome/components/mqtt/mqtt_backend_esp32.cpp b/esphome/components/mqtt/mqtt_backend_esp32.cpp
index a096408aa5..623206a0cd 100644
--- a/esphome/components/mqtt/mqtt_backend_esp32.cpp
+++ b/esphome/components/mqtt/mqtt_backend_esp32.cpp
@@ -153,11 +153,15 @@ void MQTTBackendESP32::mqtt_event_handler_(const Event &event) {
     case MQTT_EVENT_DATA: {
       static std::string topic;
       if (!event.topic.empty()) {
+        // When a single message arrives as multiple chunks, the topic will be empty
+        // on any but the first message, leading to event.topic being an empty string.
+        // To ensure handlers get the correct topic, cache the last seen topic to
+        // simulate always receiving the topic from underlying library
         topic = event.topic;
       }
       ESP_LOGV(TAG, "MQTT_EVENT_DATA %s", topic.c_str());
-      this->on_message_.call(!event.topic.empty() ? topic.c_str() : nullptr, event.data.data(), event.data.size(),
-                             event.current_data_offset, event.total_data_len);
+      this->on_message_.call(topic.c_str(), event.data.data(), event.data.size(), event.current_data_offset,
+                             event.total_data_len);
     } break;
     case MQTT_EVENT_ERROR:
       ESP_LOGE(TAG, "MQTT_EVENT_ERROR");