Cilly Aussem (German pronunciation: [ˈʦiːli̯ə ˈaʊ̯sm]; 4 January 1909 – 22 March 1963) was a German tennis player. She was the first German, male or female, to win the singles title at Wimbledon, which she did in 1931. She also won the women's single titles at the French Championships and German Championships in 1931. Aussem's coach and mixed doubles partner was Bill Tilden. They won the mixed doubles at the 1930 French Championships.