Last name:

• Junichiro Yasui (b. 1950), a Japanese politician
• Kunihiko Yasui (b. 1960), a Japanese voice actor
• Minoru Yasui (1916-1986), an Oregon born lawyer and namesake to the Supreme Court decision Yasui v. United States
• Nakaji Yasui (1903-1942), a Japanese photographer
• Yasui Sanchi (1617-1703), a Japanese professional go player
• Sotaro Yasui (1888-1955), a Japanese painter

Other:

• Yasui house, one of the four Schools (or Houses) of Go during the Edo period of Japanese history
• Yasui (Iran), a region in the country of Iran
• Yasui v. United States (1943), a decision by the Supreme Court of the United States