The incident happened at around 2200hrs on Wednesday, May 2 in Bogwood Road, Mayfield.
The victim was approached in Mayfield Road by a man driving a dark coloured Subaru Impreza. Following a short conversation he drove off, only to return a short time later in Bogwood Road where he grabbed the girl and indecently assaulted her before driving off.
He is described as white a white male in his mid 30s, stocky build, short brown hair, stubble and wearing a dark checked shirt.
The dark coloured Subaru Impreza he was driving is described as having gold alloys and a rear spoiler.
A Lothian and Borders Police spokesman said: “While the victim wasn’t injured she was understandably shaken as a result of what happened, and we are appealing for any information that can assist us in tracing the suspect.
“Anyone who recognises the description of the vehicle or the suspect, or who was in the Mayfield area last night and was approached by him, should contact police immediately.
“Anyone else with any information that can assist our inquiries should also get in touch.”
Anyone with any information should contact Lothian and Borders Police on 0131 311 3131, or Crimestoppers in confidence and complete anonymity on 0800 555 111.