"The trust that's being placed in me today is not taken lightly," Casto said. "And I don't plan to let you down."
The announcement came at City Hall, one week after Casto interviewed for the position.
Action News has learned there were 14 applicants from around the country.
The mayor and city manager weighed input from a series of community meetings and surveys, narrowing the pool to four.
Three ultimately sat for interviews.
One was a former police chief in Nevada, the second had chief experience on the East Coast, and the third was Casto.
"Chief Casto excelled during the interview process, answering each and every question with clarity and confidence," Fresno Mayor Jerry Dyer said.
Casto accepted the offer on Tuesday and says she is grateful and ready to continue her work.
"It's the community, it's our elected officials, and it's our officers that have to be prioritized for every decision, and they all have to be considered, and I promise to do that," she said.
Casto is a familiar face in the city.
She has worked at the police department for 30 years, rising from an explorer in high school to an officer and then sergeant.
Mindy Casto gives first remarks as new Fresno Police Chief
She continued to advance, eventually becoming the deputy police chief three years ago.
She was named one of the Marjaree Mason Center's Top 10 Professional Women in 2022 and now sits on the board.
Action News asked about her priorities as the new top cop.
"Number one, preservation of life is most important to us. So, continuing the violent crime reductions," she said.
"Number two, I'd like to increase our service level. There's a lot of non-emergency calls we could do better on ... and then just making sure that we constantly monitor and improve the professionalism of our officers."
Casto's appointment comes six months after former Chief Paco Balderrama resigned as details of an off-duty relationship with an officer's wife came to light.
Fresno Police Officers Association President Jeff La Blue believes Casto is the right person for the job.
"She's always looking forward, and she maintains an incredibly positive but modest approach to leadership," La Blue said.
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