diff --git a/backend/db_manager.py b/backend/db_manager.py
index 055c6f2..27c55de 100644
--- a/backend/db_manager.py
+++ b/backend/db_manager.py
@@ -32,6 +32,7 @@ class Entity:
     definition: str = ""
     canonical_name: str = ""
     aliases: List[str] = None
+    embedding: str = ""  # Phase 3: 实体嵌入向量
     attributes: Dict = None  # Phase 5: 实体属性
     
     def __post_init__(self):