Michael Kellner (born 8 May 1977) is a German politician (Alliance 90/The Greens) who has been serving as a Member of the Bundestag representing electoral constituency Uckermark – Barnim I since 2021.

[6] From 2004 to 2009, Kellner worked as chief of staff to Claudia Roth in her capacity as member of the Green Party's national leadership.

[8][9] Following his switch into a government position, he was replaced in the role during a party convention in January 2022 by Emily Büning.

[10] In early 2022, Kellner became one of the six subjects of an embezzlement investigation launched by the Berlin public prosecutor's office into the entire leadership board of the Green Party over the payment of so-called ‘corona bonuses,’ which had been paid in 2020 to all employees of the party's federal office and at the same time to its board.

[13] Kellner is married to Verena Graichen, who has been serving as deputy chair of the German Federation for the Environment and Nature Conservation (BUND) since 2019.