Wellington Zoo's 38-year-old male Chimpanzee Sam has been put down after a long battle with heart disease.

Sam was diagnosed in 2014 and his health slowly deteriorated.

He was well known at the zoo, was born in Wellington, and had a penchant for blankets and sacks.

Animal Health Care General Manager Mauritz Basson said his symptoms were having an impact on his health and social well being so they decided to euthanise him.