A magnificent partnership between Tamim Iqbal and Soumya Sarker after Mehidy Hasan Miraz's four-wicket haul helped the Tigers ease past the tourists at Sylhet International Cricket Stadium on Friday.
Bangladesh opener Liton Das gave away his wicket attempting to pull Rovman Powel, but got caught by Keemo Paul for 23.
Soumya then joined Tamim for a decisive 131-run partnership and both scored half-centuries.
Brief scores:
West Indies: 198/9 (50 overs) (Chandrapaul Hemraj 9, Shai Hope 108*, Darren Bravo 10, Marlon Samuels 19, Shimron Hetmyer 0, Rovman Powell 1, Roston Chase 8, Fabian Allen 6, Keemo Paul 12, Kemar Roach 3, Devendra Bishoo 6*; Mustafizur Rahman 0/33, Mehidy Hasan Miraz 4/29, Shakib Al Hasan 2/40, Mashrafe Bin Mortaza 2/34, Mohammad Saifuddin 1/38, Mahmudullah 0/14)
Bangladesh: 202/2 (38.3 overs) (Tamim Iqbal 81*, Liton Das 23, Soumya Sarker 80, Mushfiqur Rahim 16*; Kemar Roach 0/16, Roston Chase 0/32, Keemo Paul 2/38, Marlon Samuels 0/25, Devendra Bishoo 0/48, Fabian Allen 0/22, Rovman Powell 0/21)
Result: Bangladesh win by eight wickets.
Series: Bangladesh win 2-1
Man of the Match: Mehidy Hasan Miraz.
Man of Series: Shai Hope