diff --git a/microservice-transaction-sample/docker-compose.yml b/microservice-transaction-sample/docker-compose.yml
index 9705c96..28bbcd8 100644
--- a/microservice-transaction-sample/docker-compose.yml
+++ b/microservice-transaction-sample/docker-compose.yml
@@ -1,4 +1,3 @@
-version: "3.5"
 services:
   mysql:
     image: mysql:8.0
diff --git a/multi-storage-transaction-sample/docker-compose.yml b/multi-storage-transaction-sample/docker-compose.yml
index 4fcc755..07ea8f2 100644
--- a/multi-storage-transaction-sample/docker-compose.yml
+++ b/multi-storage-transaction-sample/docker-compose.yml
@@ -1,4 +1,3 @@
-version: "3.5"
 services:
   mysql:
     image: mysql:8.0
diff --git a/scalardb-analytics-postgresql-sample/docker-compose.yml b/scalardb-analytics-postgresql-sample/docker-compose.yml
index 6fc2844..9c6e889 100644
--- a/scalardb-analytics-postgresql-sample/docker-compose.yml
+++ b/scalardb-analytics-postgresql-sample/docker-compose.yml
@@ -1,4 +1,3 @@
-version: "3"
 services:
   analytics:
     image: ghcr.io/scalar-labs/scalardb-analytics-postgresql:3.10.3
diff --git a/scalardb-analytics-spark-sample/docker-compose.yml b/scalardb-analytics-spark-sample/docker-compose.yml
index b95a24c..2261926 100644
--- a/scalardb-analytics-spark-sample/docker-compose.yml
+++ b/scalardb-analytics-spark-sample/docker-compose.yml
@@ -1,4 +1,3 @@
-version: "3"
 services:
   spark-shell:
     build:
diff --git a/scalardb-cluster-standalone-mode/docker-compose.yaml b/scalardb-cluster-standalone-mode/docker-compose.yaml
index 94578b3..2e23d2d 100644
--- a/scalardb-cluster-standalone-mode/docker-compose.yaml
+++ b/scalardb-cluster-standalone-mode/docker-compose.yaml
@@ -1,4 +1,3 @@
-version: "3.5"
 services:
   mysql:
     image: mysql:8.1
diff --git a/scalardb-sample/docker-compose.yml b/scalardb-sample/docker-compose.yml
index 2ef1dcd..b7094bb 100644
--- a/scalardb-sample/docker-compose.yml
+++ b/scalardb-sample/docker-compose.yml
@@ -1,4 +1,3 @@
-version: "3.5"
 services:
   mysql:
     image: mysql:8.1
diff --git a/spring-data-microservice-transaction-sample/docker-compose.yml b/spring-data-microservice-transaction-sample/docker-compose.yml
index b5dd847..b9b5572 100644
--- a/spring-data-microservice-transaction-sample/docker-compose.yml
+++ b/spring-data-microservice-transaction-sample/docker-compose.yml
@@ -1,4 +1,3 @@
-version: "3.5"
 services:
   mysql:
     image: mysql:8.0
diff --git a/spring-data-multi-storage-transaction-sample/docker-compose.yml b/spring-data-multi-storage-transaction-sample/docker-compose.yml
index 5f07bbd..28ec54d 100644
--- a/spring-data-multi-storage-transaction-sample/docker-compose.yml
+++ b/spring-data-multi-storage-transaction-sample/docker-compose.yml
@@ -1,4 +1,3 @@
-version: "3.5"
 services:
   mysql:
     image: mysql:8.0