Pakistan scored 160-4 in their 20 overs after they were sent in to bat with skipper Sarfraz Ahmed (46 not out), Khalid Latif (40) and Shoaib Malik (37) amongst the runs.
They then restricted the West Indies to 144-9 with left-arm paceman Sohail Tanvir taking 3-13, also completing 50 wickets in the shortest format. Medium pacer Hasan Ali grabbed 3-49.
Andre Fletcher made 29 while Sunil Narine top-scored with 30 for the West Indies.
Pakistan had given West Indies a target of 161 runs, being made to bat first.
After a poor start, losing Sharjeel Khan early for just 2 runs, Khalid Latif and Babar Azam stabilized the flow of runs. Latif scored 40 runs before he was run out. Azam scored 19 runs.
Following their departure, Shoaib Malik and Sarfraz contributed 37 and 46 respectively.
Pakistan gave another bowling performance reminiscent of the previous game, in which they dismantled West Indies for 115-10.
Pakistan won the first match — also in Dubai — by nine wickets on Friday. The third and final match takes place in Abu Dhabi on Tuesday.
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