A Czech woman has been found alive along a remote New Zealand walking track, almost a month after her partner died in an apparent fall.

Local police say the alarm was raised after the tourist couple had not been heard from since late July.

A search was launched after the couple's car was discovered in a carpark for the Routeburn Track on the country's south island, around 70km from Queenstown.

The woman was found in a warden's hut, where she says she had been since early August.

She is said to be in good health but 'understandably upset'.

She told police her partner - who was also from the Czech Republic - fell down a steep slope on July 28th, four days after they entered the track.

The woman managed to reach him after the fall, but he is believed to have died shortly after.

Olaf Jensen, police commander for the Otago Lakes Central Area, said: "I appreciate there are a number of unanswered questions, however, until we can piece together exactly what has happened we are unable to say anything further.

"This is a highly unusual case. [It's] very unusual for someone to be missing in the New Zealand bush for such a long period without it being reported."

Police say they will be speaking to the woman to help establish exactly what happened.

They add that they have not yet been able to recover the man's body due to adverse weather conditions and the nature of the terrain.

Geoff Owen, operations manager of the Wakatipu branch of the conservation department, said: "This is a tragic incident and our condolences and sympathies are with the families of this couple."

He said his department will not be commenting further on the specifics until police have spoken to the woman.

Mr Owen said the hiking track stays open during the winter months (between July and August).

"There are significant hazards walking our southern Great Walks during the off season because of the winter weather conditions, avalanche risk and reduced facilities," he explained.