Brian David Teacher (born December 23, 1954) is an American former professional tennis player.

In 1978, at the Seiko World Super Tennis Tournament in Tokyo, Teacher upset UCLA graduates Jimmy Connors and Arthur Ashe before losing in the final to Björn Borg 6–3, 6–4.

[9] In 1980, he won the Australian Open, becoming the second Jewish player to win a men's Grand Slam Singles event (after Dick Savitt).

[10][11] With his Grand Slam victory, Teacher is one of only five American male players in the Open era to have won a single Grand Slam event (along with Michael Chang, Vitas Gerulaitis, Andy Roddick, and Roscoe Tanner).

Seven more Americans have more than one Slam (Stan Smith, Arthur Ashe, Jim Courier, Jimmy Connors, Andre Agassi, John McEnroe, and Pete Sampras).

[15] Following his playing career, he became an ATP and WTA touring coach working with Andre Agassi and Greg Rusedski.

Teacher also coached world #1 doubles players Jim Grabb, Richey Reneberg, Daniel Nestor, and Max Mirnyi.