Lew Yih Wey (born 27 June 1991) is a Malaysian swimmer, who specialised in long-distance freestyle, backstroke, and individual medley events.

[2][1] She represented her nation Malaysia at the 2008 Summer Olympics, and has won a career total of four medals (one gold and three bronze) in a major international competition, spanning the 2007 Southeast Asian Games in Bangkok, Thailand.

Three months before the Games, she produced a record-breaking effort and cleared a FINA B-cut of 4:50.52 to earn her Olympic debut at the Malaysian Open Championships in Bukit Jalil.

Her winning time from the meet also erased the national mark of 4:51.01, set by Siow Yi Ting at the 2003 Southeast Asian Games in Hanoi, Vietnam.

[4][5] Swimming as the fastest entrant in heat one, Lew attempted to chase Singapore's Quah Ting Wen and 2004 Olympic finalist Nam Yoo-sun of South Korea at the final turn of the race, but could not catch them near the wall to finish only with a third-place time and thirty-fourth overall in 4:55.83, just more than five seconds outside her national record.