Vega, 6-foot-1, smiled and waved to the crowd as outgoing titleholder Justine Pasek of Panama slipped the crown on the head during a ceremony at U.S. military base-turned-convention center in Panama.
Vega is the niece of famed merengue singer Juan Luis Guerra and the daughter of her country's representative in the 1980 Miss World pageant.
She said she too hopes to be a singer. In an entry statement to the organizing committee, she said that "music is a direct way to communicate with all the people without any race or ideological differences."
The first runner up was Miss Venezuela, the Cinderella of the contest: 22-year-old Mariangel Ruiz almost couldn't come to the competition because of financial problems in her home country. A donor finally turned up to meet the costs of her trip.
Second-runner up was South Africa's Cindy Nell, 21, a tourism promoter.
Miss Serbia and Montenegro, Sanja Papic, was third runner up and Miss Japan, Miyako Miyazaki, was fourth.
The show opened with the 72 contestants, in colorful tropical skirts and tops, introducing themselves before colonial-era buildings on the Pacific side of the Panama Canal.
The contest drew an estimated 600 million television viewers as well as nearly 7,000 Panamanians in formal wear to the new Figali Convention Center, which was recently built at the old Fort Amador, one of several military bases the United States had here as part of its Canal Zone enclave for decades.
"I am excited and anxious. I have been preparing for this for ten months," Vega before the contest.
Kai Davis of Antigua and Barbuda was named Miss Congeniality. Miss Puerto Rico, Carla Tricoli, was named Miss Photogenic.
The event gave Panama a few minutes of prime time to promote itself as a new tourist destination after decades of living under the shadow of the U.S. military, which left the country and handed over the canal on December 31, 1999.
Panama wanted to show the world it is a changed country since last hosting the pageant in 1986 under the military dictatorship of Gen. Manuel Noriega and with U.S. troops guarding the Panama Canal.
Last year, for the first time, Panama's annual income from tourism - $678 million - surpassed revenues from the canal.
On Tuesday, Panama City Mayor Juan Carlos Navarro presented the keys to the city to real estate developer and investor Donald Trump, the half-owner of the Miss Universe parent organization.
"Panama is a great country, and I'm going to come back," said Trump.
Tuesday's finals were hosted by television personalities Daisy Fuentes and Billy Bush.
By Eloy O. Aguilar