Mahmudullah was the top-scorer for Bangladesh with an unbeaten 41, while Nazmul Hossain Shanto scored 37 and skipper Tamim Iqbal a quick-fire 33.
The Tigers reached their target of 150 with 55 balls to spare.
Shoriful Islam’s best figures of 4-34 limited the West Indies to 149-9 in a match reduced to 41 overs per side due to a delayed start caused by heavy overnight showers.
Shoriful ensured the home side was never able to properly recover from early setbacks on a pitch that made free scoring difficult.
Spinner Mehidy Hasan Miraz played his part in a disciplined bowling effort with three wickets, including West Indies captain Nicholas Pooran, while pacer Mustafizur Rahman set the tone for the match when he dismissed prolific opener Shai Hope for a first-ball duck after Bangladesh captain Tamim Iqbal put the home side in to bat.
Shamarh Brooks top-scored with 33 with the next-best effort being an unbeaten 19 from Anderson Phillip in an unbroken last-wicket partnership of 39 with Jayden Seales (16*).
Shoriful went one better than Mustafizur in taking the wickets of Brandon King and Brooks in his opening over before adding the Guyanese pair of all-rounder Romario Shepherd and spinner Gudakesh Motie.
However, the coveted fifth wicket of the innings for him proved elusive as Bangladesh’s fielders dropped three catches to extend the last-wicket resistance of Phillip and Seales.
