A vehicle seat includes a base frame, a tip-up frame, and a biasing member. The base frame includes a supporting portion provided in a first side wall portion. The tip-up frame includes a supported portion pivotably connected to a second side wall portion. The supported portion is fixed to the first side wall portion while being supported by the supporting portion. The supporting portion is configured to guide the supported portion to bring the tip-up frame to a fixed position in the base frame, and to support the supported portion so as to cause the tip-up frame to be self-standing on the base frame while being disposed at the fixed position.