Mark Baliga, 41, formerly of Fishwick Parade, Preston, absconded from HMP Kirkham on Sunday, February 6.
Baliga, also known as Mark Yates, was in prison for offences including wounding with intent and police assault.
He is described as white, 5ft 9in tall, of slim build, with dark brown hair. He has brown eyes, is clean shaven and has a deep voice.
Baliga has links to the New Hall Lane, Fishwick, Ribbleton and city centre areas of Preston.
A spokesperson for the police said: "We are advising people not to approach him and call police immediately if you know where he is."
Sergeant Scott Archer said: “He is a risk due to his violent nature and history of assault. I would encourage anyone who knows where he is to come forward with information.
“Do not approach Baliga but instead call 101 immediately. In an emergency call 999.”
Alternatively you can call (01772) 209940 of email [email protected] quoting log 1423 of February 6.