A police spokeswoman told AFP that several shots were fired at a university hospital in the well-heeled southwestern Steglitz neighbourhood of the German capital.
"According to preliminary information, a patient at the hospital shot a doctor and then killed himself," she said.
"The doctor is in intensive care," the spokeswoman said, adding there was "no indication this was a terror attack".
The shooting came with Germany already on edge after four brutal attacks in the south of the country.
The Islamic State group claimed both attacks.
On Friday, nine people were killed in a shopping centre shooting spree in Munich by a German-Iranian teenager with a history of psychological problems but no apparent links to jihadists.
And a Syrian refugee killed a 45-year-old Polish woman with a large kebab knife Sunday at a snack bar in the southwestern city of Reutlingen.
