Mark Charles Wiebe (born September 13, 1957) is an American professional golfer who currently plays on the PGA Tour Champions.

His first win came in 1985 at the Anheuser-Busch Golf Classic when he beat John Mahaffey with a birdie on the first extra hole of a sudden-death playoff.

[4] Wiebe was a co-leader after 36 holes with Tom Watson at the 1987 U.S. Open[5] before shooting closing rounds of 77 and 79 to finish tied for 58th.

He defeated Bernhard Langer on the fifth hole of a sudden-death playoff with a par, after both players finished the tournament at nine-under-par.

Both players parred the first two extra holes before play was halted due to darkness, becoming the first ever Senior Open Championship to have a Monday finish.