Prasad became the third Indian to win the Faldo Series Asia Grand Final, following in the footsteps of Rashid Khan and Abhijit Chadha.
Prasad, 17, began the final day four shots behind 15-year-old Thai teenager Atiruj Winaicharoenchai, produced a near-flawless performance over the acclaimed Faldo Course at Mission Hills Dongguan.
Apart from receiving the Faldo Series Asia trophy, Prasad will also be granted an exemption into an Asian Tour event, and will also go to Faldo Series Europe Grand Final.
Six-time Major champion Faldo, Britain's most successful golfer, said, "Arjun's victory is a fitting finale to our 10th anniversary Faldo Series Asia Grand Final. It was an engrossing contest between him and Atiruj and this certainly ranks as one of the most exciting and dramatic final rounds we've seen since we launched the Series here at Mission Hills in 2007."
More From This Section
"It's been an amazing week - one that I'll remember for the rest of my life. My thanks to Nick Faldo for all his support and encouragement. I was awestruck to meet him and to see him hit shots during the clinics. That was really inspiring," Prasad said.
Two birdies and an eagle-three at the long fourth enabled Prasad to turn in four-under 32, at which point he led 15-year-old Atiruj by one.
By the time they reached the tee at the par-three 16th, Prasad had extended his advantage to two. But there he struck his only poor shot of the day, pulling his short-iron into the water and having to settle for a double-bogey that allowed Atiruj to draw level.
In the Girls' Under-21 category, victory went to American Kaitlyn Papp, a three-time Rolex Junior All-American who was joint second in last September's Faldo Series Grand Final at Sporting Club Berlin.
Fourth overall at Mission Hills, the Boys' Under-21 winner was England's Jack Yule, who also won that segment at the Faldo Series Grand Final in Berlin.
Recognised as the only global amateur series for boys and girls, the Faldo Series was established in 1996, expanding to Asia in 2006.
Today, 40 Faldo Series tournaments take place in 30-plus countries worldwide, touching more than 7,000 golfers each year. Past winners include multiple Major champions Tseng Ya-ni and Rory McIlroy.