diff --git a/docs/docs/configuration/index.md b/docs/docs/configuration/index.md
index 0489da3aa..246445575 100644
--- a/docs/docs/configuration/index.md
+++ b/docs/docs/configuration/index.md
@@ -53,6 +53,9 @@ mqtt:
   client_id: frigate
   # Optional: user
   user: mqtt_user
+  # NOTE: MQTT user can be specified with an environment variables that must begin with 'FRIGATE_'.
+  #       e.g. user: '{FRIGATE_MQTT_USER}'
+  password: password
   # Optional: password
   # NOTE: MQTT password can be specified with an environment variables that must begin with 'FRIGATE_'.
   #       e.g. password: '{FRIGATE_MQTT_PASSWORD}'
diff --git a/frigate/config.py b/frigate/config.py
index 6e6c120be..059858fbc 100644
--- a/frigate/config.py
+++ b/frigate/config.py
@@ -866,6 +866,9 @@ class FrigateConfig(FrigateBaseModel):
         # MQTT password substitution
         if config.mqtt.password:
             config.mqtt.password = config.mqtt.password.format(**FRIGATE_ENV_VARS)
+        # MQTT user substitution
+        if config.mqtt.user:
+            config.mqtt.user = config.mqtt.user.format(**FRIGATE_ENV_VARS)
 
         # Global config to propagate down to camera level
         global_config = config.dict(