Matsudaira Tadayoshi (松平 忠吉, 18 October 1580 – 1 April 1607) was the fourth son of Tokugawa Ieyasu with his concubine Saigo-no-Tsubone. His Childhood name was Fukumatsumaru (福松丸).

This article does not cite any sources. (March 2017)

When his mother died, he and his brother were adopted by Acha no Tsubone (1555-1637). His full brother, Tokugawa Hidetada, was the second shōgun. Later, Tadayoshi was adopted by Matsudaira Ietada and succeeded him as the second lord of Oshi Domain.

At the Battle of Sekigahara, he was attended by Ii Naomasa and was therefore at the forefront of the fighting. In the midst of the battle, he was shot by an Ishida gunner, but survived with a bullet wound. He was given Kiyosue Domain afterwards and remained there until his death at 1607. He was buried in Shinnyo-ji in Kakegawa.

• Father: Tokugawa Ieyasu
• Mother: Saigō-no-Tsubone
• Adopted Father: Matsudaira Ietada (Fukozu)
• Wife: Ii Masako
• Child: Umesada dai doji