diff --git a/CHANGELOG.md b/CHANGELOG.md
index d65004d..331e58d 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -3,6 +3,10 @@ All notable changes to this project will be documented in this file.
 
 The format is based on [Keep a Changelog](http://keepachangelog.com/en/1.0.0/) and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.html).
 
+## [7.3.9] - 2024-09-11
+### Fixed
+- Correct `MYSQL_DB_HOST` in readonly container.
+
 ## [7.3.8] - 2024-09-11
 ### Fixed
 - Enable `apiary_db_para_group` only when `external_database_host` not specified.
diff --git a/k8s-readonly.tf b/k8s-readonly.tf
index deedba7..90ad724 100644
--- a/k8s-readonly.tf
+++ b/k8s-readonly.tf
@@ -70,7 +70,7 @@ resource "kubernetes_deployment_v1" "apiary_hms_readonly" {
 
             env {
               name  = "MYSQL_HOST"
-              value = var.external_database_host == "" ? join("", aws_rds_cluster.apiary_cluster.*.endpoint) : coalesce(var.external_database_host_readonly,var.external_database_host)
+              value = var.external_database_host == "" ? join("", aws_rds_cluster.apiary_cluster.*.endpoint) : var.external_database_host
             }
 
             env {
@@ -113,7 +113,7 @@ resource "kubernetes_deployment_v1" "apiary_hms_readonly" {
           }
           env {
             name  = "MYSQL_DB_HOST"
-            value = var.external_database_host == "" ? join("", aws_rds_cluster.apiary_cluster.*.reader_endpoint) : var.external_database_host
+            value = var.external_database_host == "" ? join("", aws_rds_cluster.apiary_cluster.*.reader_endpoint) : coalesce(var.external_database_host_readonly,var.external_database_host)
           }
           env {
             name  = "MYSQL_DB_NAME"