diff --git a/spring-cloud-function-context/src/main/java/org/springframework/cloud/function/context/FunctionType.java b/spring-cloud-function-context/src/main/java/org/springframework/cloud/function/context/FunctionType.java
index c09cd8379..540ddf5e2 100644
--- a/spring-cloud-function-context/src/main/java/org/springframework/cloud/function/context/FunctionType.java
+++ b/spring-cloud-function-context/src/main/java/org/springframework/cloud/function/context/FunctionType.java
@@ -32,6 +32,7 @@ import reactor.core.publisher.Flux;
 import org.springframework.core.ResolvableType;
 import org.springframework.core.io.support.SpringFactoriesLoader;
 import org.springframework.messaging.Message;
+import org.springframework.util.ObjectUtils;
 import org.springframework.util.ReflectionUtils;
 
 /**
@@ -105,7 +106,14 @@ public class FunctionType {
 	}
 
 	public static FunctionType of(Type function) {
-		return new FunctionType(function);
+		FunctionType ft = new FunctionType(function);
+		if (!ft.isWrapper() && !(ft.type instanceof ParameterizedType)) {
+			Type[] genericInterfaces = ((Class<?>) function).getGenericInterfaces();
+			if (!ObjectUtils.isEmpty(genericInterfaces)) {
+				ft.type = genericInterfaces[0];
+			}
+		}
+		return ft;
 	}
 
 	public static FunctionType from(Class<?> input) {
diff --git a/spring-cloud-function-context/src/test/java/org/springframework/cloud/function/context/FunctionTypeTests.java b/spring-cloud-function-context/src/test/java/org/springframework/cloud/function/context/FunctionTypeTests.java
index 374782631..08b030239 100644
--- a/spring-cloud-function-context/src/test/java/org/springframework/cloud/function/context/FunctionTypeTests.java
+++ b/spring-cloud-function-context/src/test/java/org/springframework/cloud/function/context/FunctionTypeTests.java
@@ -16,6 +16,7 @@
 
 package org.springframework.cloud.function.context;
 
+import java.lang.reflect.ParameterizedType;
 import java.lang.reflect.Type;
 import java.util.Collections;
 import java.util.Map;
@@ -25,6 +26,8 @@ import java.util.function.Supplier;
 
 import org.junit.Test;
 import reactor.core.publisher.Flux;
+import reactor.util.function.Tuple2;
+import reactor.util.function.Tuple3;
 
 import org.springframework.core.ResolvableType;
 import org.springframework.messaging.Message;
@@ -38,6 +41,12 @@ import static org.assertj.core.api.Assertions.assertThat;
  */
 public class FunctionTypeTests {
 
+	@Test
+	public void functionWithTuples() {
+		FunctionType functionType = FunctionType.of(MyFunction.class);
+		assertThat(functionType.getType()).isInstanceOf(ParameterizedType.class);
+	}
+
 	@Test
 	public void plainFunction() {
 		FunctionType function = new FunctionType(IntegerToString.class);
@@ -324,4 +333,14 @@ public class FunctionTypeTests {
 
 	}
 
+	private static class MyFunction
+		implements Function<Tuple2<Flux<String>, Flux<Integer>>, Tuple3<Flux<String>, Flux<Integer>, Flux<Object>>> {
+
+	@Override
+	public Tuple3<Flux<String>, Flux<Integer>, Flux<Object>> apply(Tuple2<Flux<String>, Flux<Integer>> t) {
+		return null;
+	}
+
+}
+
 }