Ms. Koch-Mehrin, aged 40, also resigned from the board of the liberal Free Democratic Party (FDP).
“I am resigning my office as FDP chair in the European Parliament with immediate effect. As a consequence I will also not be a member any more of the FDP presidium.”
Ms. Koch-Mehrin neither confirmed nor denied the claims that parts of her thesis which won her a doctoral degree were plagiarized.
The University of Heidelberg is re-evaluating her academic work and may revoke the degree.
The news comes after German Defense Minister Kari-Theodor zu Guttenberg was forced to leave office after similar plagiarism charges.
“I hope to make it easier for my party to make a fresh start with a new leadership team,” she told reporters.
