diff --git a/types/sequelize/index.d.ts b/types/sequelize/index.d.ts
index 9ffda92873..4d41675ba3 100644
--- a/types/sequelize/index.d.ts
+++ b/types/sequelize/index.d.ts
@@ -5094,6 +5094,12 @@ declare namespace sequelize {
          */
         validate?: DefineValidateOptions;
 
+        /**
+         * Enable optimistic locking.  When enabled, sequelize will add a version count attribute
+         * to the model and throw an OptimisticLockingError error when stale instances are saved.
+         * Set to true or a string with the attribute name you want to use to enable.
+         */
+        version?: boolean | string;
     }
 
     /**
diff --git a/types/sequelize/sequelize-tests.ts b/types/sequelize/sequelize-tests.ts
index 9000dd92b0..c2a171109f 100644
--- a/types/sequelize/sequelize-tests.ts
+++ b/types/sequelize/sequelize-tests.ts
@@ -1572,7 +1572,20 @@ s.define( 'test', {
     underscored : true,
     freezeTableName : true
 } );
-
+s.define( 'testBooeanVersionOption', {
+    version : {
+        type : Sequelize.INTEGER,
+    }
+}, {
+    version: true
+} );
+s.define( 'testStringVersionOption', {
+    nameOfOptimisticLockColumn : {
+        type : Sequelize.INTEGER,
+    }
+}, {
+    version: "nameOfOptimisticLockColumn"
+} );
 s.define( 'User', {
     deletedAt : {
         type : Sequelize.DATE,