Eike Onnen (born 3 August 1982 in Hannover) is a German high jumper.
He finished seventh at the 2007 World Championships. He became German champion in 2005 and 2006, and represents the club LG Hannover.
His personal best jump is 2.34 metres, achieved in May 2007 in Garbsen.
He tied for third with Chris Baker in the 2016 European Athletics Championships.