Katja Ebstein (born Karin Witkiewicz; 9 March 1945) is a German singer. She was born in Girlachsdorf (now Gniewków, Poland). She achieved success with songs such as "Theater" and "Es war einmal ein Jäger". She was married to Christian Bruhn, who wrote many of her songs.

Ebstein represented Germany at the Eurovision Song Contest three times, in 1970, 1971 and 1980. She also took part in Ein Lied für Stockholm in 1975 with the song "Ich liebe dich", placing 5th in the selection. Her best performance was in 1980 when she gained second place with the entry "Theater", her other two songs "Wunder gibt es immer wieder" and "Diese Welt" each came to third places. As noted by John Kennedy O'Connor in his book The Eurovision Song Contest – The Official History, Ebstein is the most successful performer to have taken part in the contest without ever winning. She is the only singer to appear in the top three on three occasions, without winning.