Pc Christopher Gudgeon, 41, who is attached to the Met’s Central South Basic Command Unit, was charged by postal requisition on July 9, the force said.
It followed a report of sexual assault alleged to have taken place while the officer was off-duty in 2022.
The Metropolitan Police said its directorate of professional standards was aware and that Gudgeon was currently on restricted duties.
He will appear at Bromley Magistrates’ Court on July 31.