Mukai Osamu is a Japanese actor. He graduated from Meiji University, and majored in genetic engineering. While he was attending university, he worked as a bartender. He became a full-time employee there after graduation, and he became a manager later. While working as a bartender, he got into the magazine Tokyo Graffiti. A reader later recruited him to be an actor. Mukai's first main role was in the 2006 Japanese television drama Nodame Cantabile.