A bachelor who amassed a fortune by living simply left all his money to his cat after his death, The Ottawa Citizen reports.

David Harper, the shy and somewhat reclusive owner of Red the cat, died in March at the age of 79.

He left an estate worth $A1.5 million to his beloved tabby.

The United Church of Canada will administer the funds in accordance with Mr Harper's will.

It will be responsible for the three-year-old cat's care, feeding and veterinarian bills for the rest of its life.