diff --git a/packages/@aws-cdk/aws-lambda-event-sources/lib/sqs.ts b/packages/@aws-cdk/aws-lambda-event-sources/lib/sqs.ts
index 9bdba22b17cb2..4f15a5d4beb38 100644
--- a/packages/@aws-cdk/aws-lambda-event-sources/lib/sqs.ts
+++ b/packages/@aws-cdk/aws-lambda-event-sources/lib/sqs.ts
@@ -1,6 +1,6 @@
 import * as lambda from '@aws-cdk/aws-lambda';
 import * as sqs from '@aws-cdk/aws-sqs';
-import { Duration, Names } from '@aws-cdk/core';
+import { Duration, Names, Token } from '@aws-cdk/core';
 
 export interface SqsEventSourceProps {
   /**
@@ -15,7 +15,7 @@ export interface SqsEventSourceProps {
   readonly batchSize?: number;
 
   /**
-   * TThe maximum amount of time to gather records before invoking the function.
+   * The maximum amount of time to gather records before invoking the function.
    * Maximum of Duration.minutes(5)
    *
    * Valid Range: Minimum value of 0 minutes. Maximum value of 5 minutes.
@@ -39,12 +39,22 @@ export class SqsEventSource implements lambda.IEventSource {
   private _eventSourceMappingId?: string = undefined;
 
   constructor(readonly queue: sqs.IQueue, private readonly props: SqsEventSourceProps = { }) {
-    if (this.props.batchSize !== undefined) {
+    const maxBatchingWindow = this.props.maxBatchingWindow;
+    if (maxBatchingWindow !== undefined) {
+      if (queue.fifo) {
+        throw new Error('Batching window is not supported for FIFO queues');
+      }
+      if (maxBatchingWindow.toSeconds() < 0 || maxBatchingWindow.toSeconds() > 300) {
+        throw new Error(`Maximum batching window must be between 0 and 300 seconds (given ${maxBatchingWindow.toSeconds()})`);
+      }
+    }
+
+    if (this.props.batchSize !== undefined && !Token.isUnresolved(this.props.batchSize)) {
       if (this.props.maxBatchingWindow !== undefined && (this.props.batchSize < 1 || this.props.batchSize > 10000)) {
-        throw new Error(`Maximum batch size must be between 1 and 10000 inclusive (given ${this.props.batchSize})`);
+        throw new Error(`Maximum batch size must be between 1 and 10000 inclusive (given ${this.props.batchSize}) when batching window is specified.`);
       }
       if (this.props.maxBatchingWindow === undefined && (this.props.batchSize < 1 || this.props.batchSize > 10)) {
-        throw new Error(`Maximum batch size must be between 1 and 10 inclusive (given ${this.props.batchSize})`);
+        throw new Error(`Maximum batch size must be between 1 and 10 inclusive (given ${this.props.batchSize}) when batching window is not specified.`);
       }
     }
   }
diff --git a/packages/@aws-cdk/aws-lambda-event-sources/test/integ.sqs.expected.json b/packages/@aws-cdk/aws-lambda-event-sources/test/integ.sqs.expected.json
index 50af462ea8b16..e0bc8e07fece0 100644
--- a/packages/@aws-cdk/aws-lambda-event-sources/test/integ.sqs.expected.json
+++ b/packages/@aws-cdk/aws-lambda-event-sources/test/integ.sqs.expected.json
@@ -95,8 +95,7 @@
         "FunctionName": {
           "Ref": "FC4345940"
         },
-        "BatchSize": 5,
-        "MaximumBatchingWindowInSeconds": 180
+        "BatchSize": 5
       }
     },
     "Q63C6E3AB": {
diff --git a/packages/@aws-cdk/aws-lambda-event-sources/test/integ.sqs.ts b/packages/@aws-cdk/aws-lambda-event-sources/test/integ.sqs.ts
index 77de24ebcb53e..80b525e9cf13f 100644
--- a/packages/@aws-cdk/aws-lambda-event-sources/test/integ.sqs.ts
+++ b/packages/@aws-cdk/aws-lambda-event-sources/test/integ.sqs.ts
@@ -12,7 +12,6 @@ class SqsEventSourceTest extends cdk.Stack {
 
     fn.addEventSource(new SqsEventSource(queue, {
       batchSize: 5,
-      maxBatchingWindow: cdk.Duration.minutes(3),
     }));
   }
 }
diff --git a/packages/@aws-cdk/aws-lambda-event-sources/test/test.sqs.ts b/packages/@aws-cdk/aws-lambda-event-sources/test/test.sqs.ts
index f663b15aef658..abd2689668153 100644
--- a/packages/@aws-cdk/aws-lambda-event-sources/test/test.sqs.ts
+++ b/packages/@aws-cdk/aws-lambda-event-sources/test/test.sqs.ts
@@ -85,6 +85,38 @@ export = {
     test.done();
   },
 
+  'unresolved batch size'(test: Test) {
+    // GIVEN
+    const stack = new cdk.Stack();
+    const fn = new TestFunction(stack, 'Fn');
+    const q = new sqs.Queue(stack, 'Q');
+    let batchSize : number;
+
+    // WHEN
+    fn.addEventSource(new sources.SqsEventSource(q, {
+      batchSize: cdk.Lazy.number({
+        produce() {
+          return batchSize;
+        },
+      }),
+    }));
+
+    // THEN
+    expect(stack).to(haveResource('AWS::Lambda::EventSourceMapping', {
+      'EventSourceArn': {
+        'Fn::GetAtt': [
+          'Q63C6E3AB',
+          'Arn',
+        ],
+      },
+      'FunctionName': {
+        'Ref': 'Fn9270CBC0',
+      },
+    }));
+
+    test.done();
+  },
+
   'fails if batch size is < 1'(test: Test) {
     // GIVEN
     const stack = new cdk.Stack();
@@ -186,6 +218,22 @@ export = {
     test.done();
   },
 
+  'fails if batch window defined for FIFO queue'(test: Test) {
+    // GIVEN
+    const stack = new cdk.Stack();
+    const fn = new TestFunction(stack, 'Fn');
+    const q = new sqs.Queue(stack, 'Q', {
+      fifo: true,
+    });
+
+    // WHEN/THEN
+    test.throws(() => fn.addEventSource(new sources.SqsEventSource(q, {
+      maxBatchingWindow: cdk.Duration.minutes(5),
+    })), /Batching window is not supported for FIFO queues/);
+
+    test.done();
+  },
+
   'fails if batch window is > 5'(test: Test) {
     // GIVEN
     const stack = new cdk.Stack();
@@ -195,7 +243,7 @@ export = {
     // WHEN/THEN
     test.throws(() => fn.addEventSource(new sources.SqsEventSource(q, {
       maxBatchingWindow: cdk.Duration.minutes(7),
-    })), /maxBatchingWindow cannot be over 300 seconds, got 420/);
+    })), /Maximum batching window must be between 0 and 300 seconds \(given 420\)/);
 
     test.done();
   },