Masaaki Mori (森 祇晶, Mori Masaaki, born January 9, 1937) is a retired professional Japanese baseball player and manager.

Masaaki Mori
Catcher / Manager
Born: (1937-01-09) January 9, 1937 (age 87) Gifu, Gifu, Japan
Batted: Left Threw: Right
NPB debut
October 8, 1955, for the Yomiuri Giants
Last NPB appearance
October 14, 1974, for the Yomiuri Giants
NPB statistics (through 1974)
Batting average	.236
Home runs	81
Hits	1341
Teams
As player Yomiuri Giants (1955–1974) As manager Seibu Lions (1986–1994) Yokohama BayStars (2001–2002) As coach Yakult Swallows (1978–1979) Seibu Lions (1982–1984)
Career highlights and awards
21x Japan Series champion (1955, 1961, 1963, 1965-1973, 1978, 1982, 1983 1986-1992) 8× Best Nine Award (1961–1968) Japan Series MVP (1967) 2× Matsutaro Shoriki Award (1986, 1990) 11× NPB All-Star (1960–1970)
Member of the Japanese
Baseball Hall of Fame
Induction	2005

Mori played Nippon Professional Baseball from 1955–1974 as the catcher of the Yomiuri Giants. He was an eight-time Best Nine Award-winner (1961–1968) and the Japan Series MVP in 1967. He was selected to eleven Nippon Professional Baseball All-Star Games. He was nicknamed "the brains of the V9 Dynasty", as he was the main catcher of the Yomiuri Giants V9 Dynasty.

After his retirement as a player, Mori managed the Seibu Lions from 1986–1994, leading the team to 6 of the 8 Japan Series championships of the Invincible Seibu dynasty. He won the Matsutaro Shoriki Award in 1986 and 1990. Mori managed the Yokohama BayStars in 2001–2002.

Mori participated in 27 of the 73 Japan Series contested, as a player, coach, and manager, as of 2023, with him winning 21 of the 27, making him the most decorated individual in NPB history.