Ian Workman, 58, of Vale Street, Turton, was convicted of the murder of Susan Workman during an argument over their divorce settlement in April.
At Preston Crown Court he was ordered to serve at least 17-and-a-half years.
Det Supt Neil Hunter said he was pleased with the verdict as it was "a tragic crime which has left a whole family devastated by their loss".
Workman attacked his former partner while arguing in the kitchen of their matrimonial home on 7 April.
The pair were in dispute over the financial settlement of their divorce, which had seen Mrs Workman claim Â£1.4m from her husband and him offering Â£918,000.
The mother of three had been typing an account of their rows on her laptop, including descriptions of Workman's abusive language towards her and his instructions for her not to bar him from entering the house.
The final entry - "Standing, staring at me acro" - was ended abruptly by Workman's attack.
He stabbed his former wife once in the chest, before wiping the blood from his hands and the knife and calling the emergency services.
He inflicted wounds to his own stomach in a bid to disguise his crime and told police his ex-wife had attacked him.
Both were treated by paramedics at the scene but Mrs Workman died before reaching hospital.
Deputy Chief Crown Prosecutor Ian Rushton said Workman had "killed his ex-wife out of pure greed and anger because of the financial proceedings in their divorce".
"His defence, that the fatal stabbing was self inflicted by Susan Workman during a struggle after she attacked him, was an outright lie, which the jury by their guilty verdict today have rejected," he said.
Mr Hunter said it had been a "particularly challenging investigation that was built around the absence of any eye witnesses, CCTV, and only moderate forensic and pathology evidence".
He added "This is a wicked and shocking crime in which Workman violently murdered his ex-wife and then repeatedly denied his involvement.
"I am relieved for the family that he has finally been found guilty."
A spokesman for Mrs Workman's family said: "Sue did not deserve to have her life ended this way for greed and money".
"All she wanted was a reasonable settlement, so she could live a comfortable life with her boys, Ben and Nick."
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