diff --git a/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/web/servlet/DefaultServletWebServerFactoryCustomizer.java b/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/web/servlet/DefaultServletWebServerFactoryCustomizer.java
index 165bc9d96a7..702f3771b55 100644
--- a/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/web/servlet/DefaultServletWebServerFactoryCustomizer.java
+++ b/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/web/servlet/DefaultServletWebServerFactoryCustomizer.java
@@ -236,7 +236,7 @@ public class DefaultServletWebServerFactoryCustomizer
 			if (maxHttpHeaderSize > 0) {
 				customizeMaxHttpHeaderSize(factory, maxHttpHeaderSize);
 			}
-			if (tomcatProperties.getMaxHttpPostSize() > 0) {
+			if (tomcatProperties.getMaxHttpPostSize() != 0) {
 				customizeMaxHttpPostSize(factory, tomcatProperties.getMaxHttpPostSize());
 			}
 			if (tomcatProperties.getAccesslog().isEnabled()) {
diff --git a/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/web/servlet/DefaultServletWebServerFactoryCustomizerTests.java b/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/web/servlet/DefaultServletWebServerFactoryCustomizerTests.java
index 1e1fcefec70..a8e119f043b 100644
--- a/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/web/servlet/DefaultServletWebServerFactoryCustomizerTests.java
+++ b/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/web/servlet/DefaultServletWebServerFactoryCustomizerTests.java
@@ -396,6 +396,24 @@ public class DefaultServletWebServerFactoryCustomizerTests {
 		}
 	}
 
+	@Test
+	public void customTomcatDisableMaxHttpPostSize() {
+		Map<String, String> map = new HashMap<String, String>();
+		map.put("server.tomcat.max-http-post-size", "-1");
+		bindProperties(map);
+		TomcatServletWebServerFactory factory = new TomcatServletWebServerFactory(0);
+		this.customizer.customize(factory);
+		TomcatWebServer embeddedFactory = (TomcatWebServer) factory.getWebServer();
+		embeddedFactory.start();
+		try {
+			assertThat(embeddedFactory.getTomcat().getConnector().getMaxPostSize())
+				.isEqualTo(-1);
+		}
+		finally {
+			embeddedFactory.stop();
+		}
+	}
+
 	@Test
 	public void customizeUndertowAccessLog() {
 		Map<String, String> map = new HashMap<>();