The Argentine shook off his poor start to prevail in the two-hour match on outdoor clay by converting seven of his 10 break points.
"It's a very strong, very beautiful feeling,'' he said. "It was a very special match for me. I didn't have any pressure to win and it's not my culture to conform to expectations. To win a title, and against a top-10 player, carries double merits. To close the match the way I did was very emotional.''
Berlocq earned a crucial late break in the second set to turn the match in his favor before breaking Berdych four more times to win the decider.
"In the second set, when I changed my tactics I saw the ball better, committed less errors and it opened the door,'' Berlocq said.
Berlocq beat Milos Raonic in Friday's quarterfinal for his first win over a top-10 ranked opponent, and two days later he added his second by bettering the sixth-ranked Berdych.
"The first set looks easy, but it doesn't show what was going on," Berdych said. "Carlos is a big fighter and he completely changed his game, finding a way to win."
The 31-year-old Berlocq's only other career title came last year at Bastad, Sweden.