"After careful analysis of the Bundesliga season so far, Hanover 96 have made a critical decision. The club has parted ways with manager Mirko Slomka with immediate effect," the club said on their website.
Hanover said it was a difficult decision to part ways with 46-year-old Slomka, who took over in January 2010 and had 2-1/2 years left on his contract after a mainly successful tenure. However, the club are now four points above the drop zone.
The announcement was made after an assessment of the team's current situation and the prospects for the coming months following extensive discussions between club president Martin Kind, sporting director Dirk Dufner and other Hanover officials.
"It was not an easy decision to make, but we all felt that we needed to make a change," said Dufner.
Kind added: "I want to thank Mirko Slomka personally, who saved Hanover 96 from being relegated to the second division and led the club to two successive Europa League campaigns."
German media reported that 41-year-old Frank Kramer, coach of second division Greuther Fuerth, is a target to replace Slomka with Hanover hoping to find a new manager "in the coming days".