The jury at Leeds Crown Court returned a unanimous verdict on Mark Barrott after just three hours of deliberation, rejecting his plea of manslaughter on the grounds of diminished responsibility.
The 55-year-old murdered his wife Eileen at their home in Naburn Fold, Whinmoor, on August 15 last year.
The court was told during the two-week trial that Mrs Barrott, 50, had planned to leave her husband on the day she died, having suffered years of controlling behaviour at his hands.
After she tried to leave, they became entangled in a scuffle and Mr Barrott hit his wife to the head with hammer, before the pair grabbed each other’s throats.
He strangled her until she stopped breathing, but claimed had no intention of killing his wife and claimed he did not even know she was dead.
He was arrested days later after fleeing to Scotland.
It was documented during the trial that Barrott suffers from obsessive compulsive disorder (OCD) and a depressive disorder, and believed in the occult, claiming there were “dark forces” in the house.
He told the jury that he believed there was "a demon" possessing his wife at the time and wanted to “kill it”.
Barrott said he felt "detached" from himself and "reality didn't feel the same" during the incident, leading to his admission of manslaughter.
But the jury rejected the claim and unanimously agreed that he had murdered his wife.
Victim personal statements are to be heard and his sentence is to be decided at Bradford Crown Court on August 8.