Matsumoto Kōshirō (松本幸四郎?) is the stage name of a line of kabuki actors in Japan. Most of these were blood relatives, though some were adopted into the family.
Kōshirō, like other actors' names, is bestowed (or given up) at grand naming ceremonies called shūmei in which a number of actors formally change their names. Though the Matsumoto family is part of the Koraiya guild, there is a strong connection to the Naritaya guild and the Ichikawa family. It was not uncommon for members of the Matsumoto and Ichikawa families to take on names of both families over the course of their careers.
The design of the Matsumoto family mon, four flowers arranged in a diamond shape, is called yotsu-hana-bishi (四つ花菱).