A motorbike passenger has been killed on a rural Queensland highway after the rider lost control while following a police car.

A police car has been involved in a fatal crash with a motorcycle in southern Queensland.

The bike was travelling behind the marked vehicle when the rider lost control on the Warrego Highway at Wallumbilla on Monday afternoon.

Police said he and his female passenger fell from the bike, instantly killing the woman.

The man was taken to Toowoomba Hospital in a serious condition.

The motorcycle did not make contact with the police car.

The driver of the police vehicle was uninjured.

Officers from the Forensic Crash Unit and Ethical Standards Command will investigate the incident.