The Gryffindor Common Room is located in one of the castle's towers (Gryffindor Tower), the entrance to which is located on the seventh floor and is guarded by an oil painting of the Fat Lady, who is garbed in a pink silk dress. She permits entry only after being given the correct (regularly changing) password. Behind her painting is a large common room, with a fireplace, and two staircases leading up to the girls' and boys' dormitories.

There is a charm on the girls' staircase that prevents boys from using it; however, there is no such enchantment on the staircase to the boys' dormitory, allowing girls to use it whenever they wish, due to the founders' belief that girls were more trustworthy.The common room is very comfortable, and members of the Gryffindor house meet there for study groups, celebrations, or relaxation. The walls are lined with portraits, each one depicting a previous or current Head of Gryffindor.