diff --git a/backend/app/subgraphs/contact/graph.py b/backend/app/subgraphs/contact/graph.py
index 474d9f0..4026179 100644
--- a/backend/app/subgraphs/contact/graph.py
+++ b/backend/app/subgraphs/contact/graph.py
@@ -6,7 +6,7 @@ Contact Subgraph Builder
 
 from app.main_graph.graph import StateGraph, START, END
 
-from app.main_graph.state import ContactState
+from .state import ContactState
 from .nodes import create_contact_nodes
 
 
diff --git a/backend/app/subgraphs/contact/nodes.py b/backend/app/subgraphs/contact/nodes.py
index 3d2918e..57c6891 100644
--- a/backend/app/subgraphs/contact/nodes.py
+++ b/backend/app/subgraphs/contact/nodes.py
@@ -10,7 +10,7 @@ from datetime import datetime
 # 公共工具
 from ..common import MarkdownFormatter
 
-from app.main_graph.state import ContactState, ContactAction, Contact, Email
+from .state import ContactState
 from .api_client import ContactAPIClient
 
 
diff --git a/backend/app/subgraphs/dictionary/graph.py b/backend/app/subgraphs/dictionary/graph.py
index a3cebbc..bc65340 100644
--- a/backend/app/subgraphs/dictionary/graph.py
+++ b/backend/app/subgraphs/dictionary/graph.py
@@ -5,7 +5,7 @@ Dictionary Subgraph Builder - Complete
 
 from app.main_graph.graph import StateGraph, START, END
 
-from app.main_graph.state import DictionaryState
+from .state import DictionaryState
 from .nodes import (
     parse_intent,
     query_word,
diff --git a/backend/app/subgraphs/dictionary/nodes.py b/backend/app/subgraphs/dictionary/nodes.py
index a839f07..faf06c3 100644
--- a/backend/app/subgraphs/dictionary/nodes.py
+++ b/backend/app/subgraphs/dictionary/nodes.py
@@ -12,7 +12,7 @@ from ..common import (
     MarkdownFormatter
 )
 
-from app.main_graph.state import (
+from .state import (
     DictionaryState,
     DictionaryAction,
     WordEntry,
diff --git a/backend/app/subgraphs/news_analysis/graph.py b/backend/app/subgraphs/news_analysis/graph.py
index b5a016f..1aa07c8 100644
--- a/backend/app/subgraphs/news_analysis/graph.py
+++ b/backend/app/subgraphs/news_analysis/graph.py
@@ -5,7 +5,7 @@ News Analysis Subgraph Builder
 
 from app.main_graph.graph import StateGraph, START, END
 
-from app.main_graph.state import NewsAnalysisState
+from .state import NewsAnalysisState
 from .nodes import (
     parse_intent,
     query_news,
diff --git a/backend/app/subgraphs/news_analysis/nodes.py b/backend/app/subgraphs/news_analysis/nodes.py
index 0f38654..bd8e9d9 100644
--- a/backend/app/subgraphs/news_analysis/nodes.py
+++ b/backend/app/subgraphs/news_analysis/nodes.py
@@ -9,7 +9,7 @@ from datetime import datetime
 # 公共工具
 from ..common import MarkdownFormatter
 
-from app.main_graph.state import (
+from .state import (
     NewsAnalysisState,
     NewsAction,
     NewsItem,