He beat runner-up Jeev Milkha Singh (67) of India after recovering from a potentially disastrous bogey at the 15th.
Aguilar, the leader after each of the previous three rounds, finished with a total of 18-under 262 in his first career European Tour tournament win.
"I felt that things were falling apart at the 15th, especially with a player like Jeev," Aguilar said. "He is a great player and you do not want to give him any advantage with three holes to play. It feels awesome to win."
Singh, who trailed Aguilar by two shots overnight and led by one after 17 holes on Sunday, missed a 4-foot putt at the 18th that would have created a playoff.
South Africa's James Kamte (67) and Thailand's Prom Meesawat (67) shared third place at 16-under 264.
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