diff --git a/common/changes/office-ui-fabric-react/kysedate-splitbutton-dismiss-menu-on-primary-click_2018-03-29-18-40.json b/common/changes/office-ui-fabric-react/kysedate-splitbutton-dismiss-menu-on-primary-click_2018-03-29-18-40.json
new file mode 100644
index 0000000000000..6669d0e151b1f
--- /dev/null
+++ b/common/changes/office-ui-fabric-react/kysedate-splitbutton-dismiss-menu-on-primary-click_2018-03-29-18-40.json
@@ -0,0 +1,11 @@
+{
+  "changes": [
+    {
+      "packageName": "office-ui-fabric-react",
+      "comment": "Updating the split button to close the menu when the primary button is executed.",
+      "type": "patch"
+    }
+  ],
+  "packageName": "office-ui-fabric-react",
+  "email": "kysedate@microsoft.com"
+}
\ No newline at end of file
diff --git a/packages/office-ui-fabric-react/src/components/Button/BaseButton.tsx b/packages/office-ui-fabric-react/src/components/Button/BaseButton.tsx
index 0237c56493ecc..b0c79bd946e7e 100644
--- a/packages/office-ui-fabric-react/src/components/Button/BaseButton.tsx
+++ b/packages/office-ui-fabric-react/src/components/Button/BaseButton.tsx
@@ -460,7 +460,7 @@ export class BaseButton extends BaseComponent<IBaseButtonProps, IBaseButtonState
         onKeyDown={ this._onSplitButtonContainerKeyDown }
         ref={ this._splitButtonContainer }
         data-is-focusable={ true }
-        onClick={ !disabled && !primaryDisabled ? onClick : undefined }
+        onClick={ !disabled && !primaryDisabled ? this._onSplitButtonPrimaryClick : undefined }
         tabIndex={ !disabled ? 0 : undefined }
       >
         <span
@@ -474,6 +474,15 @@ export class BaseButton extends BaseComponent<IBaseButtonProps, IBaseButtonState
     );
   }
 
+  private _onSplitButtonPrimaryClick = (ev: React.MouseEvent<HTMLDivElement>) => {
+    if (this._isExpanded) {
+      this._dismissMenu();
+    }
+    if (this.props.onClick) {
+      this.props.onClick(ev);
+    }
+  }
+
   private _onRenderSplitButtonDivider(classNames: ISplitButtonClassNames | undefined): JSX.Element | null {
     if (classNames && classNames.divider) {
       return <span className={ classNames.divider } />;