Police are appealing for help to find missing Nelson man Philip Young.

The 65-year-old was walking with others near the Devil's Creek Hut area on the Wakamarina Track in Mount Richmond Forest Park in Marlborough on Thursday afternoon.

Young walked ahead of the group he was with, and had not been seen since.

Search teams, including a helicopter, looked for Young without success overnight.

The teams have returned to the site today, and a helicopter is again expected to be used.

Police are asking anyone with information of Young's whereabouts to call 03 9722150.