The 21-year-old versatile front row, comfortable at prop or hooker, made his first competitive start for the senior side against London Irish in the EDF Energy Cup in December. Mullan was later handed his first Guinness Premiership start against the same opponents in the same month.
Director of Rugby Mike Ruddock admitted he was delighted to agree a new deal with the England Under-20 international, a former Bromsgrove School pupil.
"It is fantastic news that we can announce that Matt has decided to extend this development at Sixways Stadium by signing a new two-year contract," he said.
"Matt is another product of our thriving Academy programme. Under the direction of Andrew Stanley, our academy has increased our options by developing a number of highly talented players who have all been playing first team rugby this season. Players like Tom Wood, Miles Benjamin, Chris Pennell, Jonny Arr, Joe Carlisle, Will Bowley, James Collins and, of course, Matt Mullan.
"Matt is a fine prospect indeed. He is able to play in more than one position, playing for England at under age level at prop and also at hooker and prop for Warriors. His ability to come in at more than one position is very advantageous to the team.
"At only 21 years of age he has a massive future in front of him at the club. Matt has the traditional strengths required for scrummaging and ball carrying but he is also a very modern front row forward in that his work rate is exceptional outside the scrum in all areas of the game."
Mullan said: "I'm delighted to sign a new deal at Warriors, I have really enjoyed this season and being a part of the first team squad.
"I've grown up at this club over the last five years and have been helped throughout with my development by the coaching staff. This season I have had Darren Morris and Tony Windo guiding me and they have also been fantastic for my career.
"I always wanted to play for Warriors and look forward to not only improving as a player here but also being a big part in the exciting future here at Sixways Stadium."