UPDATED: 11.53AM Police are at the scene of a grisly find in the Coromandel Peninsula.

A man's body has been found at his home in Kennedy Bay - it's believed to be days old.

Police were alerted by a family member and inquiries are underway to determine the circumstances of the man's death.

Waikato District Command Centre Senior Sergeant Robbie Herman said it's not yet known how old the man was, or how he passed.

"Police are looking at the circumstances of the death and hopefully by this afternoon we should have a better understanding of what has happened"