Morgan Birdsall, 24, was last seen in the Leyland Road area shortly before 1am this morning (Sunday, February 20) and hasn't been heard from since.
Police say they are growing "increasingly concerned for his welfare" and are appealing for help from anyone who may have information on his whereabouts.
He is also wanted in connection with an investigation into harassment, malicious communication and criminal damage.
Morgan is white, 6ft tall, of slim build, with dark brown hair which is longer on the top.
He was last seen wearing a black jacket, black tracksuit bottoms and black and white running trainers.
As well as Penwortham, he also has links to Chorley, Walton-le-Dale and Preston.
If you have seen him or know where he is, please call 101 quoting log reference 0022 of February 20.
For immediate sightings, please call 999.