Forty-seven- year-old Tony Vita stabbed his wife four times - three times in the chest and once in the back - at their family home in Baillieston, Glasgow, on September 20, last year.
The fatal wound to Crown Office manager Marion Vita's back, which severed one of her main arteries, caused her to bleed to death within minutes.
Vita, a first offender, faces life imprisonment. Judge Sean Murphy QC, who described the case as "unpleasant and distressing" deferred sentence until next month when he will determine how long Vita must spend behind bars before being eligible for parole. Vita, who worked for the Department of Work and Pensions, denied killing his wife and claimed that she had died as the result of a bizarre accident after she fell on the knife during a struggle.
He said that he had tried to kill himself after discovering that his wife had been having an affair for almost a year and didn't even realise that his wife was injured.
But, the High Court in Glasgow heard that the next-door neighbour Helen Colquitt heard three blood-curdling screams just after 8pm as she was watching Eastenders.
She said that the screams were immediately followed by a woman shouting: " No don't" followed by the sound of someone running upstairs.
In evidence Vita said that he did not realise his wife was injured and said he went upstairs and stabbed himself twice in a failed suicide bid.
But he had no explanation as to why his 48-year-old wife's smeared blood was on the front of the dressing gown he was wearing and on the legs of his glasses.
Detectives who examined the home after the murder found an entry on a calendar in the kitchen for September 20, 2013 which stated Marion = cheating lesbian whore.
Vita has also cut his wife out of family photographs and smashed a mug which said Home is where the heart is.
Mrs Vita's lover Elwira Rumniak, 34. told the court that she met her at a party in October 2012 and fell in love, Miss Rumniak told prosecutor Douglas Fairley QC that they wanted to set up home together and had talked of adopting a child.
Mrs Vita had been staying in Edinburgh with Miss Rumniak but came home to Baillieston to face her husband after confessing by text to the affair.
In a rage Vita brutally stabbed his wife four times and then left her to die.
The Vitas' 11 year-old son found her lying dying on the couch.
He said: "My mum was unconscious...her lips were quite grey.
"She was not moving at all. She was lying on the sofa, sort of on her side."
He tried opening his mum's eyes and talking to her before a 999 call was made.
The schoolboy said that Miss Rumniak had been one of Mrs Vita's "best friends", but that his dad had "suspicions" about the true extent of their relationship and he had been aware of his parents arguing.
Police officers who interviewed Vita shortly after the killing said he displayed no grief or sense of loss at the dead of his wife.
When the jury's verdict was announced Vita sat with his head bowed and as he was led away to the cells shook his head.
He will be sentenced next month.