Police are searching for a man who sexually assaulted a 12-year-old girl in Victoria's east after contacting her online.

The man organised to meet the girl in the Latrobe Valley in November last year, and picked her up in a late model dark coloured sedan, possibly a Ford Falcon, with P-plates.

After driving her to a house he sexually assaulted her, before taking her back to Churchill.

Detectives have released an image of a man they wish to speak to in relation to the incident.

Anybody with information should contact Crime Stoppers.