A missing 12-year-old girl could be hitchhiking to Sydney from her house in central NSW, police say.

Tdjanya Anderson-Rossa went missing from her house at Elong Elong, north of Dubbo, on Friday.

She had recently moved there to live with her grandfather, police said.

It was not the first time Tdjanya had gone missing, and police feared she might have attempted to hitchhike back to Sydney, where her parents live.

Tdjanya is described as 150 centimetres tall, with a slim build, olive complexion, dark brown shoulder-length hair and brown eyes.

At the time she disappeared, she was wearing blue denim jeans, a black and grey waist-length coat with fur collar and white joggers.

Anyone with information can contact Dubbo Police Station on 6881 3299 Crime Stoppers on 1800 333 000.