Two people have been rescued from a light plane crash in a national park near Camden in Sydney's south-west.

The plane came down in a river near Burragorang Road, at Nattai National Park, after engine failure.

NSW Ambulance said two patients had been winched to safety and were being taken to hospital.

Neither was seriously hurt.

Police received reports the small Jamaroo plane had been forced to make an emergency landing about 3:15 p.m.

"Emergency services immediately commenced a search for the aircraft, locating it in bushland in the Nattai Conservation Park," a NSW Police statement said.

"Two people travelling in the plane were winched to safety by a NSW Ambulance helicopter.

"The plane remains in situ, partly submerged in a river in the national park."

The national park is home to dense bushland, rugged hiking trails and sandstone cliffs.