Members of the police commission and Beck's family were on hand as the mayor officially announced his pick at an afternoon news conference.
"Choose the man who could have reached you when you were 17. Choose the man who you think can change the course of a young person's life. Charlie Beck is that man," said Mayor Villaraigosa.
"He is a police officer who is tough on crime and he is a leader with deep respect and understanding of the police officers under his command," he added.
Beck said he will continue the success of his predecessor and will not let the city down. He is credited with helping cleanup the image of the scandal-plagued Rampart division and said he spent hours trying to convince the mayor that he was the right choice.
It appeared Villaraigosa needed an extra day to make his decision. He was originally supposed to make his announcement on Monday, but he postponed it a day.
"The future of this organization is in our hands at this moment," said Beck. "We have come so far in the last seven years and it is so important that we drive those changes that we've made, that we take them and we put them into the DNA of this organization so that never again will it depend solely on the leader to make the difference."
Beck has deep roots in police work. His wife is a former Sheriff's deputy, his daughter is an LAPD officer in Hollywood, his sister is a former LAPD detective, his father is a retired LAPD deputy chief, and Beck's son is expected to soon graduate from the Police Academy.
"He is very familiar with the organization and the needs of the organization," said Paul Webber, President of the Los Angeles Police Protective League. "He has developed relationships over the years. He is going to leverage those relationships not only within city government, but within the community, to make sure that we get the resources that we need."
Beck, who says he's humbled by his selection, says that he will not go back to the violent crime and lack of confidence in the police from the 1990s. He says the city is long past that style and philosophy of policing.
"And we can never go back to that, and I've come to that recognition the hard way," said Beck. "I didn't learn it in school; I didn't read it in a book. I learned it in places like Nickerson Garden, I learned it in places like Ramona, I learned it on the streets of Rampart, I learned it all over this city, and I will never forget that lesson."
At a community meeting in Exposition Park Tuesday night, Beck's appointment was met with praise and optimism.
"I have a working relationship with the 77th police department so I've seen Chief Beck there from time to time. He seems to be a very personable person, a very open person. He has a real close knit base with the community," said Keith Johnson, a youth football coach.
"The other police -- I've talked to quite a few of them, I've made some phone calls -- everyone seems to be thrilled with the decision," said Sandra Davis, an employee at the South L.A. WorkSource Center.
If the L.A. City Council ratifies the mayor's selection, Beck will become the city's 55th police chief.
Bratton's last day on the job was Saturday. He's going on to a new job in the private sector.
The two other finalists were Assistant Chief Jim McDonnell and Deputy Chief Michel Moore. The mayor met for a second time with all three finalists at his official residence in Hancock Park on Sunday, spending about an hour with each of them.
Eyewitness News report Subha Ravindhran contributed to this report.