Tony Vita, 47, 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, said.
He described the case as "unpleasant and distressing" and 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.
Mrs Vita's lover Elwira Rumniak, 34, told the court that she met her at a party in October 2012 and fell in love.
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.
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.