The Men-in-Green restricted India to 264 for eight, defending 267 in the high octane clash.
At the end of 40 overs, India were in commanding position with 215/5 on board. They continued to sail smoothly until the 45th over.
With only 26 runs remaining in last five overs, Umer Khan sent Shubham Sharma back to pavilion and brought Pakistan back in contention.
Ammad Butt bowled an economical over, just leaking two runs, put Indians under serious pressure, before Umer stuck once again which put India on back foot in 48th.
Pakistan had to defend eight runs from the final over but Ammad Butt showed superb skill and conceded just four runs. He also took a wicket, which restricted India to 264.
Earlier, Haider Ali and Omair bin Yousuf added 90 runs before the first wicket, after Pakistan opted to bat first at Sher-e-Bangla National Cricket Stadium.
Omair smashed two sixes and stroked three boundaries for his 97-ball-66 while Haider Ali scored 43.
Saif Badar remained unbeaten with 47 as Pakistan posted 267/7 runs on the scoreboard.