Gisela Kallenbach worked as an assistant and laboratory manager from 1969 to 1990. In 1990, she was elected a city councilor in Leipzig, and in the same year she took a job as a clerk in the municipal department of environmental protection. She held this position until 2000. Between 2000 and 2003, she was in Kosovo, working as International Mayor in UN mission.
In 2004, Kallenbach was elected Member of the European Parliament and remained an MEP until 2009. During that period she was member of the Group of the Greens/European Free Alliance, member of the Committee on Regional Development, member of the Delegation for relations with the countries of south-east Europe, member of the Delegation for relations with the countries of south-east Europe.