Having won the toss, Guernsey put Malta into bat and their bowlers showed little mercy to their opponents as they bowled them out for just 74 in 18.2 overs.
Martin Dale Bradley returned excellent figures of 4-9 while Adam Martel and Ed Robinson took two wickets each.
Maltese captain Mehboob Ali was one of only two players from his side to reach double figures as the opener hit 25 from 26 balls.
Muhammad Ajmal scored 17 not out as Malta struggled to cope with the Guernsey attack.
But in reply Guernsey got off to a shaky start as they lost opener Josh Butler for a duck and Tom Nightingale for 4 to leave them on 13-2 in the third over.
However, Lucas Barker and Matt Stokes steadied the innings with a 25-run third wicket stand before Barker was caught for 12.
Stokes, who hit a game-high 51 against Sweden, continued his good form with 24 not out as he and skipper Ollie Nightingale (28) guided Guernsey home with a 32-run partnership as the islanders reached 78-4 off 11.2 overs.