Daniela Nedelcu, 40, was last seen at Piccadilly train station at 11am on Monday 7 September 2015.
Daniela is described as being 5ft 5in tall, of slim build and has short hair. She was last seen wearing grey, pink and purple jacket and black trainers.
Police Constable Helen McNeill of North Manchester division said: “Police and Daniela’s family are extremely worried about her. She is originally from Romania and speaks little English and this behaviour is out of character.
“She often goes to the Ashton, Longsight and Manchester city centre areas and I would appeal to anyone who sees her to contact police.”
Anyone with information about Daniela’s whereabouts should call police on 101 or the independent charity Crimestoppers, anonymously, on 0800 555 111.