Larry Stefanki (born 23 July 1957 in Elmhurst, Illinois), is an American tennis coach and former professional tennis player. As a player, he played for nine years from 1979 reaching a career high ranking of 35 and winning one ATP tournament in singles and three in doubles. He is one of three Stefanki brothers to have played on the varsity tennis team at the University of California at Berkeley. However, he is more renowned as a tennis coach, having trained such players as John McEnroe, Marcelo Ríos, Yevgeny Kafelnikov and Tim Henman amongst others. Ríos and Kafelnikov both achieved their number 1 tennis rankings while under his guidance.

Stefanki is currently the coach of Fernando González, after taking over this role from Horacio de la Peña in May 2006. Under Stefanki the Chilean reached back-to-back finals in Vienna, the Madrid Masters and Basel in 2006 and the 2007 Australian Open final —a tournament in which he eased past the likes of Lleyton Hewitt, James Blake, Rafael Nadal and Tommy Haas— which saw González, 26, reach a career-high of 5 in the ATP Rankings.