Garcia, who led by five as the day began at the El Cortijo Club de Campo, shot a 1-over 73 in the final round to win by four strokes over Italy's Emanuele Canonica. He finished at 13-under-par 275.
This is the 22-year-old's second victory of the season, having captured the PGA Tour's Mercedes Championships in January.
Garcia appeared ready to run away with the title early at Gran Canaria. He opened birdie-eagle before bogeys on Nos. 4 and 7 saw him make the turn at 1-under. A double bogey at No. 12 kept the field within reach, but Canonica was only able to muster an even-par 72.
Im very happy, said Garcia, who is now fourth on the Order of Merit (money list). Admittedly, I didnt play as well as Id have liked to on the final day` but I hung in there because I wanted to win. It doesnt matter how you do it, everyone is always simply going to remember that I won.
More from Sergio on his win.
England's Greg Owen finished alone in third place at 8-under after also posting 72. Sweden's Carl Pettersson and 17-year-old Spanish amateur Rafel Cabrera tied for fourth, a stroke further back.
Cabrera, who is is being touted as 'The Next Sergio,' played in the final round alongside his countryman. He played solidly in matching Garcia's 73.
The day's only round in the 60s belonged to reigning U.S. Open champion Retief Goosen, who had a 67 and finished in a tie for eighth with David Gilford at 4-under.
Full-field scores from the Canarias Open de Espana