The Communist Party of Germany (Opposition) (German: Kommunistische Partei Deutschlands (Opposition) or KPD (Opposition), generally abbreviated as KPO or KPDO) was a communist opposition organisation established at the end of 1928 and maintaining its existence until 1939 or 1940. After the rise of Adolf Hitler and the Nazi Party to power in January 1933, the KPO existed only as an illegal and underground organization. The group initially sought to modify, later to replace, the mainstream Communist Party of Germany (KPD) headed by Ernst Thälmann. The KPO was the first national section affiliated to the International Communist Opposition (ICO).
The KPO represented the so-called Right Opposition in the KPD in distinction to the Trotskyist or Trotskyist-sympathising Left Opposition and the pro-Comintern centre faction. It was led by Heinrich Brandler and August Thalheimer who had led the KPD between 1921 and 1923. They were expelled from the KPD after organising a meeting to combat what they saw as corruption in their party after its central leader Ernst Thälmann defended a protégé, John Wittorf, from charges of theft despite his guilt. Thälmann was deposed by the Central Committee only to be reinstated by Joseph Stalin through the agency of the Comintern.
The secretary of the Hamburg organization of the KPD was found to have embezzled 2,000 marks from the party treasury for his own use. When accountants from national party headquarters discovered the crime, they were threatened with expulsion from the party by party leader Thälmann if they exposed the theft. The Comintern got wind of the scandal which led to a crisis in the German party with the Central Committee acting to remove Thälmann, with Thälmann joining in the unanimous vote.