diff --git a/Service/Sources/EDOHostService+Private.h b/Service/Sources/EDOHostService+Private.h
index 08d98eb..fd4b40c 100644
--- a/Service/Sources/EDOHostService+Private.h
+++ b/Service/Sources/EDOHostService+Private.h
@@ -16,12 +16,12 @@
 
 #import "Service/Sources/EDOHostService.h"
 #import "Service/Sources/EDOObject+Private.h"
+#import "Service/Sources/EDOObject.h"
 
 NS_ASSUME_NONNULL_BEGIN
 
 @class EDOExecutor;
 @class EDOHostPort;
-@class EDOObject;
 @protocol EDOChannel;
 
 /** The internal use for sending and receiving EDOObject. */
diff --git a/Service/Sources/EDOInvocationMessage.h b/Service/Sources/EDOInvocationMessage.h
index c4b2256..5c13fc3 100644
--- a/Service/Sources/EDOInvocationMessage.h
+++ b/Service/Sources/EDOInvocationMessage.h
@@ -17,6 +17,7 @@
 #import "Service/Sources/EDOServiceRequest.h"
 
 #import "Service/Sources/EDOObject+Private.h"
+#import "Service/Sources/EDOObject.h"
 #import "Service/Sources/EDORemoteException.h"
 
 NS_ASSUME_NONNULL_BEGIN
diff --git a/Service/Sources/EDOParameter.h b/Service/Sources/EDOParameter.h
index b8cd857..e79c2d8 100644
--- a/Service/Sources/EDOParameter.h
+++ b/Service/Sources/EDOParameter.h
@@ -17,8 +17,6 @@
 #import <Foundation/Foundation.h>
 #import <objc/runtime.h>
 
-#import "Service/Sources/EDOObject.h"
-
 NS_ASSUME_NONNULL_BEGIN
 
 /** Check if the given C-string type is an Id type. */