Sean Miller (29) trashed the taxi and punched the driver (70) to the ground, leaving him black and blue and "pumping blood" on a south Dublin street.
He had claimed that the cabbie made an "offensive remark" on seeing him holding hands with his partner in the back seat.
The gay couple had been returning home from a night out when Miller took offence at the alleged remark about them and set upon the driver.
The victim, Cathal Hawkes, denied making any remark.
Sentencing Miller, Judge Catherine Murphy said she found the accused had "blatantly lied" in evidence.
Miller, of Mount Anville Park, Goatstown, was found guilty of assault causing harm to Mr Hawkes and €1,500 worth of damage to his car at Northumberland Road, Dublin 4 on December 14, 2011.
He had denied the charges, maintaining he kicked the car wheel once, the driver then attacked him first, and that he pushed him away once in self-defence.
During the trial at Dublin District Court, neither Miller nor his partner, Niall Byrne, could elaborate on their claim of an alleged offensive remark, which they said prompted Mr Byrne to get out of the moving cab.
At the sentencing, the court heard a compensation offer was made to Mr Hawkes and rejected.
During the trial, the court heard Mr Hawkes picked Miller and Mr Byrne up at Nassau Street.
On the way, the accused made a statement to his partner, telling him: "I am not a c***."
Miller then leaned across to Mr Byrne, put his arm around him and said: "You know I love you."
Mr Byrne suddenly opened the door and got out. Mr Hawkes said: "Good God, man, what are you doing?"
Miller got out after him, the driver asked "what's going on here?" and the accused threw a five euro note in.
Miller kicked the front passenger door, jumped across the bonnet and flattened the BMW sign before punching the driver's window and door.
Mr Hawkes jumped out and said "calm down", but the accused started swinging his fists and punched him "a ferocious belt" to the face.
He fell to the ground "pumping blood" and Miller walked away.
He was in "terrible shock", with blood pouring on to his jumper, when gardai arrived.
Since the incident, his car had been written off in an unrelated hijacking and he had now given up taxi work.