Set a smallish target of 148 for victory, the Nepal were pegged back early when they lost opener Dipin Shresta and star batsman Gyanendra Mall for a blob.
But opener Anil Kumar Mandal held fort to score a stroke-filled 79 to spur Nepal to the victory target in just 35 overs.
Antim Thapa provided a late flourish to the innings clubbing an unbeaten 37 to cap off a memorable day for himself after he had done his bit with the ball claiming figures of 4-19 to help Nepal bowl out Afghanistan for a paltry 147 off 37.3 overs.
Earlier, opting to bat first, Afghanistan made a steady start to reach 134 four but lost a heap of wickets after that to surrender the initiative to Nepal. Javid Ahmadi stood out from the ruins for Afghanistan with a enterprising 58 coming off just 79 balls.
Brief Scores:Afghanistan: 147 all out (37.3 overs). Nepal: 148 for 4 in 35 overs.