John Alloway (70) was last seen about 2am yesterday, walking near the address where he was staying at in Antimony Cres.
He was not at the Antimony Cres address or with any other relatives in the Cromwell area when family members checked on him about 7am today.
Police say his disappearance is out of character and they have concerns for his well-being given he has a medical condition.
He appears to have no additional clothing or medication with him.
Mr Alloway may be wearing a blue or black jacket and dark coloured long pants. He is described as being of medium build and approximately 184cm in height. He is slightly balding with wispy grey hair and is clean shaven.
Anyone with information who might have seen Mr Alloway in the Cromwell area should contact police on 03 471-5002, or call 111 if they should see him.
It is possible Mr Alloway is making his own way back to the North Island, as he had intended return today.