diff --git a/spring-web/src/main/java/org/springframework/web/util/ContentCachingResponseWrapper.java b/spring-web/src/main/java/org/springframework/web/util/ContentCachingResponseWrapper.java
index 41fc196d678..f3596993daa 100644
--- a/spring-web/src/main/java/org/springframework/web/util/ContentCachingResponseWrapper.java
+++ b/spring-web/src/main/java/org/springframework/web/util/ContentCachingResponseWrapper.java
@@ -164,7 +164,13 @@ public class ContentCachingResponseWrapper extends HttpServletResponseWrapper {
 	@Override
 	public void setHeader(String name, String value) {
 		if (HttpHeaders.CONTENT_LENGTH.equalsIgnoreCase(name)) {
-			this.contentLength = toContentLengthInt(Long.parseLong(value));
+			if (value != null) {
+				this.contentLength = toContentLengthInt(Long.parseLong(value));
+			}
+			else {
+				this.contentLength = null;
+				super.setHeader(name, null);
+			}
 		}
 		else {
 			super.setHeader(name, value);
diff --git a/spring-web/src/test/java/org/springframework/web/filter/ContentCachingResponseWrapperTests.java b/spring-web/src/test/java/org/springframework/web/filter/ContentCachingResponseWrapperTests.java
index 25ddffbc3b6..5fd7a300c9f 100644
--- a/spring-web/src/test/java/org/springframework/web/filter/ContentCachingResponseWrapperTests.java
+++ b/spring-web/src/test/java/org/springframework/web/filter/ContentCachingResponseWrapperTests.java
@@ -270,6 +270,17 @@ class ContentCachingResponseWrapperTests {
 				.withMessageContaining(overflow);
 	}
 
+	@Test
+	void setContentLengthNull() {
+		MockHttpServletResponse response = new MockHttpServletResponse();
+		ContentCachingResponseWrapper responseWrapper = new ContentCachingResponseWrapper(response);
+		responseWrapper.setContentLength(1024);
+		responseWrapper.setHeader(CONTENT_LENGTH, null);
+
+		assertThat(response.getHeaderNames()).doesNotContain(CONTENT_LENGTH);
+		assertThat(responseWrapper.getHeader(CONTENT_LENGTH)).isNull();
+	}
+
 
 	private void assertHeader(HttpServletResponse response, String header, int value) {
 		assertHeader(response, header, Integer.toString(value));