A sanitary washing apparatus according to an embodiment includes a base plate and a body part. The base plate has a pair of mounting holes that corresponds to a pair of through-holes formed on an upper surface of a toilet bowl and is mounted on the upper surface of the toilet bowl by inserting fastening members mounted on the pair of mounting holes through the pair of through-holes. The body part incorporates a functional component that includes a washing nozzle, and is mounted on the toilet bowl via the base plate. Furthermore, a mounting part for the body part is formed only between the pair of mounting holes on the base plate.