Hanaa Bennis, 13, was last seen at 5.30pm on Thursday, 4 December close to the Morrisons supermarket on King Street, Acton.
Hanaa is described as 5ft 5ins tall, with long brown hair and brown eyes.
When last seen she was wearing her school uniform comprising of a navy blazer, white shirt, grey tie, black trousers and black shoes.
She was also wearing a black 'Superdry' raincoat with a pink logo on the back.
She may have travelled to the Hounslow area.
Anyone who has seen Hanaa is asked to contact Ealing police via 101 quoting reference 14MIS043804.
