Police have charged a couple with holding a man captive for six months and forcing him to clean their house in the central western New South Wales town of Bathurst.

It is believed the 26-year-old man moved in with the couple at their home on the outskirts of Bathurst as a lodger in February.

He has told officers he was locked inside a cubbyhouse in the lounge room and denied food or medical treatment.

Police say he had his mobile phone confiscated and was repeatedly assaulted, at times with a baseball bat.

He was found in an emaciated and dehydrated state, suffering rib and spinal fractures, a punctured lung and a fractured jaw, and weighing just 40 kilograms.

The man, whose normal body weight was 70 kilograms, was rushed to Bathurst Base Hospital and later transferred to Westmead Hospital.

A 41-year-old man and 46-year-old woman were arrested yesterday and refused bail.

They will face court in October on 27 charges of kidnapping, assault and grievous bodily harm.