Peter David Heyn (born 26 June 1945) is a former Sri Lankan cricketer who played in 18 unofficial Test matches from 1966 to 1976, and two One Day Internationals in the 1975 World Cup.

Heyn began his cricket career at St Peter's College in Colombo, where he represented the school from 1961 to 1964, captaining in 1964.

His first-class debut was in 1964, playing 50 matches in total and compiling four hundreds (the highest being 136 against Indian Universities at Bangalore in December 1975).

As Sri Lanka were unlikely to attain full test status at the time, Heyn emigrated to England in 1976.

In 1981 he played 4 games for Berkshire in the Minor Counties Championship - unfortunately, further appearances were not possible due to work & family commitments.