David Merwin (August 17, 1936 - July 3, 1960) is an American sprint canoer who competed in the late 1950s.
He was eliminated in the heats of the K-1 1000 m event at the 1956 Summer Olympics in Melbourne.
The top finishers in each heat moved to the finals.
Merwin was a member of the Alpha Tau Omega fraternity at Cornell University in Ithaca, NY, where he was also a member of the University's crew.
He graduated in 1958, but, while training for the 1960 Olympics, died in an automobile accident near Greenville, Pennsylvania, July 3, 1960 while returning from a vacation in Canada with a friend.