diff --git a/.env.example b/.env.example
index 44ef9b936..4e9bf7b02 100644
--- a/.env.example
+++ b/.env.example
@@ -49,5 +49,11 @@ CYPHER_ENDPOINT=http://localhost:11434/v1
 MEMGRAPH_HOST=localhost
 MEMGRAPH_PORT=7687
 MEMGRAPH_HTTP_PORT=7444
+# Memgraph authentication credentials
+# Leave MEMGRAPH_USERNAME empty (or omit it) if your Memgraph instance doesn't require authentication
+# If authentication is enabled, provide both username and password
+# Common defaults: username=neo4j, password=password (or your custom credentials)
+MEMGRAPH_USERNAME=
+MEMGRAPH_PASSWORD=
 LAB_PORT=3000
 TARGET_REPO_PATH=.
diff --git a/codebase_rag/config.py b/codebase_rag/config.py
index eccf7bab5..ee34df4b3 100644
--- a/codebase_rag/config.py
+++ b/codebase_rag/config.py
@@ -42,6 +42,8 @@ class AppConfig(BaseSettings):
     MEMGRAPH_HOST: str = "localhost"
     MEMGRAPH_PORT: int = 7687
     MEMGRAPH_HTTP_PORT: int = 7444
+    MEMGRAPH_USERNAME: str | None = None
+    MEMGRAPH_PASSWORD: str | None = None
     LAB_PORT: int = 3000
     MEMGRAPH_BATCH_SIZE: int = 1000
 
diff --git a/codebase_rag/main.py b/codebase_rag/main.py
index 0586a9f3c..a70eea106 100644
--- a/codebase_rag/main.py
+++ b/codebase_rag/main.py
@@ -785,6 +785,8 @@ async def main_async(repo_path: str, batch_size: int) -> None:
         host=settings.MEMGRAPH_HOST,
         port=settings.MEMGRAPH_PORT,
         batch_size=batch_size,
+        username=settings.MEMGRAPH_USERNAME,
+        password=settings.MEMGRAPH_PASSWORD,
     ) as ingestor:
         console.print("[bold green]Successfully connected to Memgraph.[/bold green]")
         console.print(
@@ -870,6 +872,8 @@ def start(
             host=settings.MEMGRAPH_HOST,
             port=settings.MEMGRAPH_PORT,
             batch_size=effective_batch_size,
+            username=settings.MEMGRAPH_USERNAME,
+            password=settings.MEMGRAPH_PASSWORD,
         ) as ingestor:
             if clean:
                 console.print("[bold yellow]Cleaning database...[/bold yellow]")
@@ -930,6 +934,8 @@ def export(
             host=settings.MEMGRAPH_HOST,
             port=settings.MEMGRAPH_PORT,
             batch_size=effective_batch_size,
+            username=settings.MEMGRAPH_USERNAME,
+            password=settings.MEMGRAPH_PASSWORD,
         ) as ingestor:
             console.print("[bold cyan]Exporting graph data...[/bold cyan]")
             if not _export_graph_to_file(ingestor, output):
@@ -970,6 +976,8 @@ async def main_optimize_async(
         host=settings.MEMGRAPH_HOST,
         port=settings.MEMGRAPH_PORT,
         batch_size=effective_batch_size,
+        username=settings.MEMGRAPH_USERNAME,
+        password=settings.MEMGRAPH_PASSWORD,
     ) as ingestor:
         console.print("[bold green]Successfully connected to Memgraph.[/bold green]")
 
diff --git a/codebase_rag/mcp/server.py b/codebase_rag/mcp/server.py
index 9e05e36e0..0004318e1 100644
--- a/codebase_rag/mcp/server.py
+++ b/codebase_rag/mcp/server.py
@@ -103,6 +103,8 @@ def create_server() -> tuple[Server, MemgraphIngestor]:
         host=settings.MEMGRAPH_HOST,
         port=settings.MEMGRAPH_PORT,
         batch_size=settings.MEMGRAPH_BATCH_SIZE,
+        username=settings.MEMGRAPH_USERNAME,
+        password=settings.MEMGRAPH_PASSWORD,
     )
 
     # CypherGenerator gets config from settings automatically
diff --git a/codebase_rag/services/graph_service.py b/codebase_rag/services/graph_service.py
index ad4c69e76..146174cb7 100644
--- a/codebase_rag/services/graph_service.py
+++ b/codebase_rag/services/graph_service.py
@@ -9,9 +9,24 @@
 class MemgraphIngestor:
     """Handles all communication and query execution with the Memgraph database."""
 
-    def __init__(self, host: str, port: int, batch_size: int = 1000):
+    def __init__(
+        self,
+        host: str,
+        port: int,
+        batch_size: int = 1000,
+        username: str | None = None,
+        password: str | None = None,
+    ):
         self._host = host
         self._port = port
+        self._username = username
+        self._password = password
+        # Validate authentication: both username and password must be provided together
+        if (self._username is None) != (self._password is None):
+            raise ValueError(
+                "Both username and password are required for authentication. "
+                "Either provide both or neither."
+            )
         if batch_size < 1:
             raise ValueError("batch_size must be a positive integer")
         self.batch_size = batch_size
@@ -32,7 +47,19 @@ def __init__(self, host: str, port: int, batch_size: int = 1000):
 
     def __enter__(self) -> "MemgraphIngestor":
         logger.info(f"Connecting to Memgraph at {self._host}:{self._port}...")
-        self.conn = mgclient.connect(host=self._host, port=self._port)
+        # Build connection parameters - only include username/password if provided
+        connect_params = {
+            "host": self._host,
+            "port": self._port,
+        }
+
+        # Only add authentication parameters if both username and password are provided
+        # This allows connection to Memgraph instances without authentication
+        if self._username is not None:
+            connect_params["username"] = self._username
+            connect_params["password"] = self._password
+
+        self.conn = mgclient.connect(**connect_params)
         self.conn.autocommit = True
         logger.info("Successfully connected to Memgraph.")
         return self
diff --git a/realtime_updater.py b/realtime_updater.py
index 9267b1819..53bc290d5 100644
--- a/realtime_updater.py
+++ b/realtime_updater.py
@@ -94,6 +94,8 @@ def start_watcher(
         host=host,
         port=port,
         batch_size=effective_batch_size,
+        username=settings.MEMGRAPH_USERNAME,
+        password=settings.MEMGRAPH_PASSWORD,
     ) as ingestor:
         updater = GraphUpdater(ingestor, repo_path_obj, parsers, queries)