Mahela Jayawardene's side ripped through a woeful Windies batting line up, dismissing them for just 80 runs in the 31st over, with right-arm paceman Farveez Maharoof doing most of the damage, taking 6 wickets for 14 off nine overs.
22-year-old Mahroof's remarkable figures were in stark contrast to the West Indies batting totals, with only Wavel Hinds, 28 off 86 balls, and captain Brian Lara, 13 off 35, managing to reach double figures.
Extras were the second highest scorer for the Windies with 17.
Lara, whose side lost a wicket in each of the first three overs of their innings, tried to remain upbeat after the devastating loss which sees them placed in Group A alongside Australia, England and India in the main draw.
"Last time no one gave us any chance but we won the title," said Lara, referring to the West Indians’ win in the 2004 Champions Trophy in England.
"I feel we have the guys and the ingredients to do so again despite what happened. We have to be positive and pick ourselves up for the next stage where all teams start afresh.
"I still think we can do it though we batted poorly. We need to assess our batting collapses and address it or we're not going to last long in this tournament," the 37-year-old Trinidadian added.
"The only good thing is that all eight teams start with zero points."
Sri Lanka's big win sent out a warning to other Champions Trophy aspirants, especially those who they join in Group B – New Zealand, Pakistan and South Africa.
"We have not put pressure on ourselves by saying we'll win the tournament, but we will make sure we compete," Sri Lankan captain Jayawardene said.
Lasith Malinga (L) dismisses West
Indian Shivnarine Chanderpaul
After turning in a superb bowling and fielding effort, Sri Lanka had an early scare when opening batsman Upul Tharanga was bowled off the first ball of their innings by Windies quick Fidel Edwards.
However after that initial set-back, Sri Lankan evergreen Sanath Jayasuriya (45 off 47), and the captain himself (34 off 35), put on a winning partnership of 83 from 79 balls to easily seal the match in just the 14th over.
"Winning is a very good habit. When we lose we look for what mistakes we've made, but even when we're winning we're looking to see what mistakes we made and how we can improve our game," Jayawardene added.
"That has been the battle for us in the last six months. If we're really critical about the performance against the West Indies we'd say that we bowled too many no-balls," he added, referring to the Sri Lankan total of 10 no-balls in 31 overs.
Having already accounted for Bangladesh and Zimbabwe in qualifying, the dominant win was Sri Lanka's tenth consecutive one-day victory and they go into the Champions Trophy full of confidence.
The West Indies play Australia first up in the Group stage at Mumbai on October 18, while Sri Lanka start their campaign in the main tournament with a match against Pakistan in Jaipur on October 17.