An Eastern Bay of Plenty man's death in Whanganui Prison has been ruled a suicide by Coroner Tom Scott.

A Coroner's report has been released into the death of 70-year-old Donald Gisborne, who was sentenced to life in prison for killing in his wife Kanok-On Gisborne in 2008.

In 2008, police were called to a domestic at the couple's home and found Gisborne beside his wife's body.

The following day he was arrested and charged with his wife's murder.

The details of how Gisborne died in prison have been suppressed.

No recommendations have been made to the courts.