A man suffered fractures to his face in an assault outside The Parish, Kirkgate, in the early hours of Friday.
It is believed the victim had been involved in an altercation at around 2.45am on February 3.
During the assault the injured man was kicked when on the ground.
Police want to speak to another man in connection with the incident.
He is described as white, aged 40, 5ft 8in to 5ft 10in, of lean build and with a shaved or bald head.
Witnesses to the serious assault are asked to contact DC Mark Willetts of Huddersfield CID on 101.
A police spokesperson said: “Police in Huddersfield are appealing for witnesses after a serious assault outside the Parish public house on Kirkgate, on Friday 3 February.”
In unrelated investigations, police would like to speak to the people pictured in the image gallery below. The people pictured in the images may be witnesses as well as suspects. If you recognise anyone, contact police on 101 quoting the reference number on the image caption.