Carballo, a European Tour transplant, finished at 6-under-par 274 for a two-shot victory over three players.
'I still can't believe I won,' said Carballo, a 27-year-old Argentine. 'I didn't think I would ever win but I'm happy that I did.
'To win any Nationwide Tour tournament would be a thrill, but to do it in Latin America makes it even more special. Earning a Nationwide Tour card and having the opportunity to fulfill a goal of mine to play on the PGA TOUR is beyond words.'
Jim McGovern (66), Hunter Haas (70) and Patrick Sheehan (71) shared second place at 4-under 276. Third-round leader Marc Yurnesa had a 73 and slipped into a tie for fifth place with Camilo Benedetti (65) at 277.
Carballo had six birdies over his first 13 holes. He made a bogey at the 16th, but atoned with a 15-foot birdie putt at the 17th. His closing bogey at No. 18 didn't matter.
'My goal at the beginning of the day was to shoot 4- or 5 under, and I was able to do that,' said Carballo. 'I played so well today under tough conditions and a lot of pressure.'
Carballo is the third Latin American to win on the Nationwide Tour after Paraguay's Angel Franco and Keoke Cotner and Esteban Toledo of Spain. His victory came at the same course, Panama Golf Club, where another famous Argentine golfer won: Hall of Famer Roberto De Vicenzo.
'Just winning is great,' said Carballo. 'But winning in the same place where one of the best golfers from Argentina and the world won is a great thrill.'
Jeremy Anderson shot a 67 to move from a tie for 18th place into a tie for seventh place at 2-under 278. He was joined there by Chris Nallen (68), Tim Wilkinson (70), Richard Johnson (70) and Gary Christian (72).