Paul Abbott was jailed for life with a 15-year minimum term earlier this year after he admitted murdering his wife Jackie.
The brutal attack saw him batter her at least 16 times with a hammer while chasing her around their home in Netherton on December 11 last year.
Prison chiefs have said Abbott was found dead in a Worcestershire jail on Sunday - exactly one year to the day that he had killed his wife of 28 years.
The 57-year-old was jailed at Wolverhampton Crown Court in July, after admitting a single charge of murder at an earlier hearing.
This afternoon a Prison Service spokesman confirmed Abbott's death and said an independent probe into the circumstances is under way.
The spokesman said: "HMP Long Lartin prisoner Paul Abbott died in custody on Sunday, December 11.
"As with all deaths in custody there will be an independent investigation by the Prisons and Probation Ombudsman."
An inquest is expected to take place at Worcestershire Coroner's Court.
The court heard how Abbott's gambling, jealousy and controlling behaviour had dominated the pair's relationship.
It emerged his wife had also been the victim of 'sporadic' violence from him - culminating in the frenzied attack which killed her in the house in Lodge Crescent.
Gambling losses and a row over tickets to an Elvis tribute act sparked the ferocious assault which saw him act 'like a wild dog'.
The couple - who ran a business near their home selling fishing, darts and snooker equipment with their two sons - had repeatedly argued over his gambling and her drinking during the final year of the victim's life, prosecutor Robert Price said.
His sons, who had been at the family's business in Hurst Lane, Brierley Hill, found their 54-year-old mother's bloodstained body in the back garden.
Oldest son Martyn then knocked his father to the ground outside after Abbott swung a punch at him.
Abbott had immediately admitted his guilt when arrested, the court was told.
When the killer was arrested he told police: "She was a perfect girl. I flipped and lost the plot.
"I wouldn't do that to a dog. It was despicable. I lost control like a wild dog.
"I have got to live with this. A bloke can do a lot of damage to a woman.
"A bloke can overpower a woman. So why did I need a hammer? I don't know. I don't know why I did it."