Baerbock said the murder was a serious violation of German law and sovereignty and would seriously burden Russian-German relations.
"We therefore summoned the Russian ambassador," she said. "We told him that two members of the embassy staff would be declared persona non grata."
Earlier in the day a German court found Russian citizen Vadim Krasikov guilty of the August 2019 murder of Tornike Khangoshvili, an ethnic Chechen of Georgian nationality, in a central Berlin park, and sentenced him to life imprisonment.
The court said his crime had been ordered by the Russian government.
Khangoshvili was shot dead at close range in broad daylight on Aug. 23, 2019.
Police arrested Krasikov later the same day.