Captain Nehimiah Perry captured the wickets of Atul Wassan and Atul Bedade in the first over and Kenny Benjamin claimed Robin Singh from the first ball of the next over as India slumped to four for three.
West Indies, who arrived in Hong Kong only nine hours before they played their first match on Saturday, looked in trouble after scoring just 75.
But they gained the upperhand with those early strikes.
The Hong Kong Sixes, a big-hitting, six-a-side version of cricket with matches reduced to five overs each, attracted eight test-playing nations.
In the semifinals, Laurie Williams took three wickets to help West Indies to a 24-run win over holders South Africa. Williams dismissed Adrian Kuiper, Bradley Player and captain Hansie Cronje to rip the heart out of the innings.
India skipper Sanjay Manjrekar hit a swashbuckling 44, including four sixes, in the one-wicket semifinal win over World Cup holders Sri Lanka.