diff --git a/types/cookie-session/index.d.ts b/types/cookie-session/index.d.ts
index a77732aad1..fdbbbc650f 100644
--- a/types/cookie-session/index.d.ts
+++ b/types/cookie-session/index.d.ts
@@ -103,7 +103,7 @@ declare namespace CookieSessionInterfaces {
         /**
          * Represents the session for the given request.
          */
-        session?: CookieSessionObject;
+        session?: CookieSessionObject | null;
 
         /**
          * Represents the session options for the current request. These options are a shallow clone of what was provided at middleware construction and can be altered to change cookie setting behavior on a per-request basis.