Answer
The current mayor of Bonn is Katja Dörner , who started in Nov 1, 2020. Katja Dörner is a member of Alliance'90/The Greens Katja Dörner replaced Ashok-Alexander Sridharan.
Katja Dörner is a German politician of the Alliance 90/The Greens who has been serving as mayor of Bonn since 2020.