Ursula Haverbeck was sentenced in August on charges of incitement relating to her assertion that Auschwitz was a work camp and was never used for mass extermination.
Her appeal was rejected by a regional court in Celle in the state of Lower Saxony, which ruled that the judgement by the state court in Verden at the end of August last year was legally sound and should be implemented.
The Verden court found Haverbeck guilty of incitement in eight cases, sentencing her to two years without suspension.
Haverbeck has been convicted of incitement several times. The German authorities prosecute Holocaust denial on the basis of a 1985 law and its many revisions banning incitement.