The English national was dropped off by his family at the Lake Sylvan car park early yesterday to walk the Lake Sylvan-Rockburn-Sugarloaf-Routeburn circuit.
When he didn't arrive at the Routeburn Road end last night his wife contacted police.
A helicopter and crew equipped with night vision and infra-red equipment started searching in the early hours of this morning but were unable to locate him.
Police said weather conditions were poor with snow flurries on alpine sections of the route and rain, wind and cloud.
Two ground teams of search and rescue volunteers went into the route from opposite ends and this morning met at the junction of the Rockburn Track and the Sugarloaf Pass Track.
They continued up the Rockburn Track and at 9:30am found the man alive and well about 20 minutes walk further along the track.
Some 14 people were involved in the ground and air search for the man, who lives with his wide and child in Australia.
Senior sergeant John Fookes praised the efforts of search and rescue volunteers who searched through the night in poor conditions.
