Rinse the jasmine rice under cold water until the water runs clear.
In a saucepan, combine the rinsed rice, coconut milk, water, sugar, and salt. Stir well.
Bring to a boil over medium heat. Once boiling, reduce the heat to low, cover, and simmer for about 18-20 minutes, or until the rice is tender and the liquid is absorbed.
Remove from heat and let it sit, covered, for an additional 5 minutes.
Fluff the rice with a fork and gently fold in the diced mango.