McConkey - who could not explain why he attacked the defenceless monk - will be eligible for parole after three years and four months in jail.
Mr Lieu died in a hospital two weeks after being bashed during a meditation session early in the morning at Bibra Lake Regional Park in Perth's South.
He suffered four broken ribs, a ruptured liver and a fractured skull.
The court was told Wednesday that McConkey attacked the monk after going on an alcohol and amphetamine binge following an argument with his girlfriend but there was no explanation of what motivated him.
Judge Stephen Hall described the attack as an unprovoked, serious and savage assault on a person who did not have the capacity to retaliate.
McConkey was originally charged with murder but later plead guilty to the lesser charge of manslaughter, which carries a maximum penalty of 20 years jail.
