Dean Ambler was given an 18-month sentence over the attack on his victim during the incident at in the Midland pub, Normanton, Wakefield.
Leeds Crown Court heard the victim was attacked when he tried to intervene in an altercation between Amber and one of his friends around 11.30pm in May last year.
Nigel Jamieson, prosecuting, said Ambler lunged at the man and knocked him to the floor.
He added: “They struggled and the defendant bit his left ear, causing excruciating pain.”
Ambler also bit the victim’s left index finger before being pulled away by others.
Police were called but the victim initially refused to make a complaint.
He eventually decided to make a complaint after realising the severity of his injuries the next day.
His ear lobe was partially detached and required nine stitches.
The victim also had to spend two nights in hospital after the wound to his finger became infected.
He had to undergo an operation and required plastic surgery. Mr Jamieson said the victim was unable to work for five weeks as a result of his injuries.
Ambler, of Dodsworth Crescent, Normanton, was arrested and interviewed and initially denied biting anybody during the incident.
He later pleaded guilty to unlawful wounding.
The court heard Ambler has previous convictions for assault and affray.
Christopher Morton, mitigating, said the incident happened at a time when the pub was extremely busy over the bank holiday period.
He said the incident had stemmed from an earlier fracas in the pub toilets over a cigarette but Ambler could not remember much of what happened because of the amount of alcohol he had drunk.
Mr Morton said Ambler and the victim had seen each other since the attack and his client had apologised for what he had done.
The barrister added: “There is no more animosity between them.”