Prentice took to a podium in Edmonton to say he wants to be the next premier because he believes the province has a bright future ahead of it.
"I am running because I believe Alberta has before it right now an opportunity to achieve great things," Prentice said Wednesday. "It's going to take discipline and it's going to take focus, but we will do this."
Prentice said it will take a clear plan, strong leadership and hard work.
For six years between 2004 and 2010, Prentice was the MP for Calgary Centre-North and served under Prime Minister Stephen Harper in three cabinet portfolios.
He left politics three years ago to take an executive position with CIBC, but was persuaded to run for the leadership of the Alberta Tories after Alison Redford quit in March amid spending scandals and accusations of poor leadership.
With about half the Tory caucus supporting him, Prentice, 57, is considered the candidate to beat.
The only other declared candidate so far is former Alberta infrastructure minister Ric McIver of Calgary.
During his first public speech as a candidate, Prentice emphasized his roots in the province. He moved to Alberta with his parents and four siblings when he was a child and said he knew he had come home when he saw the Rocky Mountains for the first time.
"I am running fundamentally ... because I love this place and I think I have a duty to make it better and to leave it better."
David Hancock is acting as interim premier until the leadership vote is held in September.
Other potential candidates, including cabinet ministers Doug Horner, Diana McQueen and Jonathan Denis, have announced they will not run.
Jobs Minister Thomas Lukaszuk has hinted for weeks he might enter the race, but at this point he has just over a week to decide. Nominations close May 30.