Imogen Oona Lehmann (born 30 December 1989) is a Swiss-German curler.

Oona Lehmann played her junior career in her native Switzerland.

The following year, she was a member of the national junior championship team.

Oona Lehmann played lead for the German team (skipped by Rainer Schöpp) that won a bronze medal at the 2010 European Mixed Curling Championship.

After that, Oona Lehmann joined Schöpp's sister, Andrea's team at the third position.