Karen Krantzcke (1 February 1946 – 11 April 1977) was an Australian tennis player. She achieved a world top ten singles ranking in 1970. In her short career, she made the quarterfinals or better at each of the four Grand Slam championships in both singles and doubles. She also won the Australian Open in doubles, and assisted Australia to victory in the Federation Cup. At the age of 31, Krantzcke died from a heart attack while jogging.