Detectives are searching for Richard Watkins after the school boy was attacked by a group of men in Samuel Street, off New Hall LAne, at around 11.10pm on Sunday, March 10.
Watkins' last known address is Merrick Avenue in Preston, but police said his whereabouts since the attack are unknown.
Det Insp Roger Ashcroft, of South Preston Police, said: “We were called at around 11:30pm on Sunday, March 10th after the boy, 14, attended Royal Preston Hospital with knife wounds to his arm, hand, leg and ankle.
"It is believed he had been attacked by a group of men. His injuries are serious but not life threatening.
"We want to speak to Richard Watkins in connection with this nasty assault and I would appeal to anyone who knows where he may be to get in touch.
"I would also urge Watkins himself to come and talk to us if he sees this appeal."
Three men, aged 21, 22 and 24 were arrested on suspicion of GBH with intent in connection with the incident.
The 21-year-old has been bailed until April 8 pending further enquiries and the 22 and 24-year-old suspects have been released under investigation pending further enquiries.
The stabbing was one of a number of knife crimes that forced Lancashire Police to launch stop and search operations in the city last week.
More than 150 people and 25 vehicles were searched in the areas of Fishwick and St Matthews, between Monday, March 11 and Thursday, March 14.
Anyone with information should contact police on 101 quoting log 1478 of March 10 or email [email protected]