Obata Masamori, also known as Obata Nobusada, was a Japanese samurai warrior. He is known as one of the "Twenty-Four Generals of Takeda Shingen". He was the son of Obata Toramori, and came from western Kozuke province. He fled Kozuke and joined the Takeda around 1560. Masamori would later become the lord of Kaizu castle in Shinano province.Coming from a province conquered by the Takeda, Masamori belonged to the sakikata-shu (the group of vanquished enemies) within the Takeda establishment, but proved himself repeatedly by loyal service. He fought for the Takeda at the Mimasetoge (1569).