Osmond Roy Greig, 43, pleaded guilty to murder in a Brisbane court on Tuesday over the fatal 2016 attack on Daryl Corcoran.

Greig used the axe to break a window to get into the home at Alexandra Hills, southeast of Brisbane, about 11.25pm on November 22, 2016.

His ex-wife, Mr Corcoran and three children were asleep in the house at the time.

After stabbing Mr Corcoran, Greig turned the knife on himself, cutting his own arms, legs and throat, the Brisbane Supreme Court was told.

Describing the attack as "anger-filled" and his actions as appalling, Justice Ann Lyons said it was very clear Greig intended to kill Mr Corcoran.

She told Greig that nothing could erase the loss of Mr Corcoran's life for his family and "their profound and ongoing grief".

"Nothing can ever explain your appalling actions on that night," she added.

"You took another man's life in a violent, sustained, premeditated, planned and anger-filled attack in front of your estranged wife."

Justice Lyons sentenced Greig to life imprisonment for murder, saying, "You will forever be serving a sentence of life imprisonment."

"For the rest of your life you are subject to that sentence."

Greig will be able to apply for parole after serving 20 years.

Justice Lyons also sentenced Greig to a concurrent 10-year jail term for burglary.

Australian Associated Press