Matsudaira Tadamasa (松平 忠昌?, 21 January 1598 – 20 September 1645) was a Japanese daimyō of the early Edo period.
Tadamasa was the second son of Yūki Hideyasu. He became the clan leader and head of Fukui Domain in 1622 when his older brother was banished to Ogiwara in Bungo Province.
He had a magnificent upper residence (kamiyashiki) constructed outside Edo Castle.