William Gratwicke Heasman (9 December 1862 – 24 January 1934) was an English cricketer active in the 1880s and 1890s, making fifteen appearances in first-class cricket.
Born at Angmering, Sussex, Heasman was a right-handed batsman and right-arm fast bowler, who played first-class cricket for Sussex, and minor counties cricket for Berkshire.