Susi-Lisa Erdmann (later Plankensteiner, born 29 January 1968) is an East German-German luger and bobsledder who competed from 1977 to 1998 in luge, then since 1999 in bobsleigh.

She is one of only two people to ever win a medal in both bobsleigh and luge at the Winter Olympics; Italy's Gerda Weissensteiner is the other.

Beside the Olympics in luge, Erdmann won ten medals at the FIL World Luge Championships, including seven golds (Women's singles: 1989, 1991, 1997; Mixed team: 1990, 1991, 1993, 1995) and three silvers (Women's singles: 1995, 1996; Mixed team: 1989).

Erdmann switched to bobsleigh in 1998, competing both at the Winter Olympics and the FIBT World Championships.

It was announced on 7 September 2009 FIL website that Erdmann had married Italian luger Gerhard Plankensteiner on 28 August 2009.