"He was found guilty of murder and disturbing the peace of the dead," said presiding judge Birgit Wiegand at the regional court in the eastern city of Dresden.
Detlev Günzel, 57, went on trial in August over the killing of Polish-born Wojciech Stempniewicz, a business consultant, at the defendant's home, a bed-and-breakfast inn in the mountain town of Hartmannsdorf-Reichenau near the Czech border, in November 2013.
The defendant sat impassively with arms folded as the verdict was read out.
The court had heard that the accused had cut the body into small pieces and buried them in his garden but there was no evidence that he ate any part of his victim.
State attorneys had sought 10 and a half years in prison for the defendant, a trim, soft-spoken father of three adult children whom neighbours described as friendly, generous and unfailingly polite.
Lawyers representing the family of Stempniewicz, 59, had requested a 15-year sentence, usually the maximum in a murder case.
But prosecutors said they stopped short of this demand because Stempniewicz said he wanted to die.
The men came across each other in October 2013 on a website for slaughter and cannibalism fantasies billed as the "#1 site for exotic meat" and boasting more than 3,000 registered members.