"It's the biggest dream to achieve this," said Ibarguen. "I'm very happy and proud."
The two-time world champion Ibarguen was hot-favourite going into the Rio Games after winning 36 of her last 37 competitions excluding qualifying events.
The 32-year-old soared past 15m twice and appeared in total control after producing her best jump in the fourth round, though she failed in her plan to break Ukraine's Inessa Kravets's world record of 15.50m set in 1995.
Ibarguen's young challenger Yulimar Rojas took silver with a 14.98m jump and became the first woman from the South American country to win a medal in athletics.
The 20-year-old also became the youngest female winner of a triple jump Olympic medal, capping her meteoric rise in an event she only started two years ago.
Kazakhstan's London Olympics champion Olga Rypakova pulled off the two best jumps of her season, but her 14.74m in the fifth round was only good enough for bronze.
(Editing by Greg Stutchbury)
