The 21-year-old has signed a two-year deal at the club.
“He play in a number of positions and will add depth to our squad for 2016. He has a good attitude and is keen to learn and develop.”
Owens made 66 appearances for Widnes, scoring 30 tries and kicking 122 goals.
“I have played for Widnes since I was 12 and really enjoyed the experience and my time there,” he said.
“But it got to a point where my game time was limited so I asked Denis Betts and the coaching staff if I could go out and play somewhere else for the 2016 season.
“They agreed and the opportunity came up to play for St Helens. I felt it was the best option for me and I cannot wait to kick on and start the season.
“It’s a bit alien for me as I have always had the same coach and group of players around me. I’m excited to meet the players here and see how Keiron Cunningham and his coaching team do things.
“I know I have to earn the right to play, especially with talent the club has – and that means proving to the players and the coaches I deserve to play.
“If I do that, then I need work hard and play well to hold on to that spot.
“Before then, my focus is on pre-season, getting fit and developing my skills.”