diff --git a/packages/aws-cdk-lib/aws-lambda/lib/function.ts b/packages/aws-cdk-lib/aws-lambda/lib/function.ts
index eabc03cab3a38..1f6bcdc9c1274 100644
--- a/packages/aws-cdk-lib/aws-lambda/lib/function.ts
+++ b/packages/aws-cdk-lib/aws-lambda/lib/function.ts
@@ -1085,6 +1085,9 @@ export class Function extends FunctionBase {
    * function and undefined if not.
    */
   private getLoggingConfig(props: FunctionProps): CfnFunction.LoggingConfigProperty | undefined {
+    if (props.logFormat !== undefined && !Object.values(LogFormat).includes(props.logFormat as LogFormat)) {
+      throw new TypeError(`'${props.logFormat}' is not a legal LogFormat type.`);
+    }
     if ((props.applicationLogLevel || props.systemLogLevel) && props.logFormat !== LogFormat.JSON) {
       throw new Error(`To use ApplicationLogLevel and/or SystemLogLevel you must set LogFormat to '${LogFormat.JSON}', got '${props.logFormat}'.`);
     }