Martyn John Woodroffe (born 8 September 1950[1]) is a Welsh swimmer.

He won a silver medal at the 1968 Olympic Games.

[3] He represented Wales at the 1966 British Empire and Commonwealth Games in Kingston, Jamaica, and 1970 British Commonwealth Games in Edinburgh, Scotland, winning one silver and two bronze medals at the latter.

[4] In 1968 he represented Great Britain at the Olympics in Mexico City in five swimming disciplines - 100 m, 200 m butterfly, 200 m, 400 m individual medley, and in the 4×100 m medley relay.

[1] He won the silver medal in the 200 m butterfly in a time of 2 minutes 9.0 seconds, behind Carl Robie of the United States.