diff --git a/core/spring-cloud-stream/src/main/java/org/springframework/cloud/stream/function/BindableFunctionProxyFactory.java b/core/spring-cloud-stream/src/main/java/org/springframework/cloud/stream/function/BindableFunctionProxyFactory.java
index 2e75bf079..9f7f3c023 100644
--- a/core/spring-cloud-stream/src/main/java/org/springframework/cloud/stream/function/BindableFunctionProxyFactory.java
+++ b/core/spring-cloud-stream/src/main/java/org/springframework/cloud/stream/function/BindableFunctionProxyFactory.java
@@ -58,20 +58,31 @@ public class BindableFunctionProxyFactory extends BindableProxyFactory implement
 
 	private final SupportedBindableFeatures supportedBindableFeatures;
 
+	private final boolean functionExist;
+
 	private GenericApplicationContext context;
 
 	BindableFunctionProxyFactory(String functionDefinition, int inputCount, int outputCount, StreamFunctionProperties functionProperties) {
-		this(functionDefinition, inputCount, outputCount, functionProperties, new SupportedBindableFeatures());
+		this(functionDefinition, inputCount, outputCount, functionProperties, new SupportedBindableFeatures(), true);
+	}
+
+	BindableFunctionProxyFactory(String functionDefinition, int inputCount, int outputCount, StreamFunctionProperties functionProperties, boolean functionExist) {
+		this(functionDefinition, inputCount, outputCount, functionProperties, new SupportedBindableFeatures(), functionExist);
+	}
+
+	BindableFunctionProxyFactory(String functionDefinition, int inputCount, int outputCount, StreamFunctionProperties functionProperties, SupportedBindableFeatures supportedBindableFeatures) {
+		this(functionDefinition, inputCount, outputCount, functionProperties, supportedBindableFeatures, true);
 	}
 
 	BindableFunctionProxyFactory(String functionDefinition, int inputCount, int outputCount, StreamFunctionProperties functionProperties,
-			SupportedBindableFeatures supportedBindableFeatures) {
+			SupportedBindableFeatures supportedBindableFeatures, boolean functionExist) {
 		super(null);
 		this.inputCount = inputCount;
 		this.outputCount = outputCount;
 		this.functionDefinition = functionDefinition;
 		this.functionProperties = functionProperties;
 		this.supportedBindableFeatures = supportedBindableFeatures;
+		this.functionExist = functionExist;
 	}
 
 	@Override
@@ -104,7 +115,7 @@ public class BindableFunctionProxyFactory extends BindableProxyFactory implement
 	}
 
 	protected String getFunctionDefinition() {
-		return this.functionDefinition;
+		return this.isFunctionExist() ? this.functionDefinition : null;
 	}
 
 	protected String getInputName(int index) {
@@ -188,4 +199,8 @@ public class BindableFunctionProxyFactory extends BindableProxyFactory implement
 	public void setApplicationContext(ApplicationContext applicationContext) throws BeansException {
 		this.context = (GenericApplicationContext) applicationContext;
 	}
+
+	public boolean isFunctionExist() {
+		return functionExist;
+	}
 }
diff --git a/core/spring-cloud-stream/src/main/java/org/springframework/cloud/stream/function/FunctionConfiguration.java b/core/spring-cloud-stream/src/main/java/org/springframework/cloud/stream/function/FunctionConfiguration.java
index 56685e688..bfb624708 100644
--- a/core/spring-cloud-stream/src/main/java/org/springframework/cloud/stream/function/FunctionConfiguration.java
+++ b/core/spring-cloud-stream/src/main/java/org/springframework/cloud/stream/function/FunctionConfiguration.java
@@ -436,9 +436,9 @@ public class FunctionConfiguration {
 			Map<String, BindableProxyFactory> beansOfType = applicationContext.getBeansOfType(BindableProxyFactory.class);
 			this.bindableProxyFactories = beansOfType.values().toArray(new BindableProxyFactory[0]);
 			for (BindableProxyFactory bindableProxyFactory : this.bindableProxyFactories) {
-				String functionDefinition = bindableProxyFactory instanceof BindableFunctionProxyFactory
+				String functionDefinition = bindableProxyFactory instanceof BindableFunctionProxyFactory && ((BindableFunctionProxyFactory) bindableProxyFactory).isFunctionExist()
 						? ((BindableFunctionProxyFactory) bindableProxyFactory).getFunctionDefinition()
-								: this.functionProperties.getDefinition();
+								: null; /*this.functionProperties.getDefinition();*/
 
 				boolean shouldNotProcess = false;
 				if (!(bindableProxyFactory instanceof BindableFunctionProxyFactory)) {
@@ -898,7 +898,7 @@ public class FunctionConfiguration {
 						sourceFunc.isConsumer() ||
 						(!sourceFunc.getFunctionDefinition().equals(outputBindingName) && applicationContext.containsBean(outputBindingName))) {
 
-					BindableFunctionProxyFactory proxyFactory = new BindableFunctionProxyFactory(outputBindingName, 0, 1, this.streamFunctionProperties);
+					BindableFunctionProxyFactory proxyFactory = new BindableFunctionProxyFactory(outputBindingName, 0, 1, this.streamFunctionProperties, sourceFunc != null);
 					((GenericApplicationContext) this.applicationContext).registerBean(outputBindingName + "_binding_out",
 						BindableFunctionProxyFactory.class, () -> proxyFactory);
 				}