Before becoming foreign minister in 1998, Fischer was engaged in the left movement (post-)68 in Frankfurt, including participation in protest marches becoming violent. He has worked as a taxi driver and bookshop clerk, minister for the environment in the German state Hesse (1985-1987 and 1991-1994), member of the Bundestag 1983-1985 and again since 1994 (as chair person of the Greens). His 1985 appointment as minister in Hesse was the first in Germany for a Greens politician and caused uproar because he was wearing tennis shoes during his oath of office. These shoes are now on display in the German Historic Museum in Bonn.
Fischer was born in Gerabronn (Baden-Württemberg). He has an honorary degree (Dr. h.c.) from the University of Haifa.
Fischer was married four times, to Edeltraud (1967-1984), Inge (1984-1987), Claudia (1987-1999), and Nicola (1999-2003), all marriages ending in divorce.