Robert J. Lunn (born April 24, 1945) is an American professional golfer who played on the PGA Tour in the 1960s and 1970s.
Lunn was born in San Francisco, California. He was the 1963 U.S. Amateur Public Links champion. He turned pro in 1965 and won six times on the PGA Tour. In 1968, he was named Most Improved Golfer of the Year by Golf Digest. He earned $102,711 and finished 11th on the money list that year after winning two tournaments in a row – the Memphis Open Invitational and the Atlanta Classic. Lunn's best years in professional golf were 1968-1972 when he appeared in the top 60 on the money list in each of those years.