In August 1939, Edith Keller (17 years old), along with Klaus Junge (15), Wolfgang Unzicker (14), Rudolf Kunath (15) and Karl Krbavic (17), played in Jugendschachwoche Fürstenwalde near Berlin. During World War II, she won the 2nd German Women's Championship at Bad Oeynhausen 1942. In next German Women's Championship, she took 3rd, behind Gertrud Jürgens and Maja Schlemmer, at Vienna 1943, and tied for 7-8th at Bad Krynica 1943 (the 4th General Government chess tournament, Josef Lokvenc won).
After the war, Edith Keller-Hermann has been German Women's Champion in 1947, 1948, 1951, 1952 and 1953, and also Eastern German Women's Champion in 1950, 1952, 1956, 1957 and 1960.
In 1949/50, she was Women's World Championship Challenger in Moscow, and tied for 5-7th there (Lyudmila Rudenko won). In 1951, she tied for 11-12th in Dortmund (Albéric O'Kelly de Galway won) but drew with Efim Bogoljubow and won games against Rossolimo and Puc. In 1952, she tied for 4-6th in Moscow (Women’s Candidates Tournament; Elisabeth Bykova won)). In 1955, she took 3rd in Moscow (Women’s Candidates Tournament; Olga Rubtsova won). In 1959, she tied for 4-5th in Plovdiv (Women’s Candidates Tournament; Kira Zvorykina won).
Edith Keller-Hermann played for East Germany in several Women's Chess Olympiads; at first board at Emmen 1957, Split 1963, Oberhausen 1966, and at second board at Lublin 1969. She won three team bronze medals and two individual medals (silver in 1957, and bronze in 1963).