The force said women using roads through the west London beauty spot, with permission, have repeatedly been shouted at by men who believe they should not be driving there.
The “frightening” incidents have seen cyclists bang on cars and throw water over them, while women were driving alone or with children.
The Met Police said in a statement on X: “We have had several reports from female motorists who are authorised to drive on the closed roads in Richmond Park of abuse and harassment, including banging on the vehicle and throwing water over the car, by male cyclists, as they believe incorrectly that they are not authorised.
“This behaviour is not acceptable and has caused upset, anxiety and fear.
“Please be aware that permit holders are authorised to use the closed roads. We conduct regular checks on vehicles to ensure the drivers are authorised. Thank you.”
Richmond Park’s manager Paul Richards said: “We are extremely concerned that female drivers, including those driving alone or with children, have reported frightening harassment by a small number of males on cycles, such as shouting and banging on their car, and spraying the car with water.
“Harassment is a crime, and it is not tolerated. The incidents have been reported to the police.”
Sawyers Hill - a road that runs through the sprawling 2,500 acre park - is closed to public traffic at the weekend to “provide a welcoming environment for all visitors”.
But Mr Richards said: “A small number of vehicles are authorised to use the roads - including park staff, parents dropping children off at the Ballet School and visitors accessing the stables.”