The Scots are a point ahead of Gibraltar who have played a game more, and qualification for the second round looks increasingly likely.
It took an own goal to break the deadlock, as a long ball by Iain Scholefield cannoned off two Gibraltar defenders and eluded the goalkeeper but Alan Forsyth, Kenny Bain, Chris Grassick and Dan Coultas added further strikes.
“The result was better than the performance, we really only played some relaxed hockey in the final ten minutes when we scored three goals,” said Scotland manager Eugene Connolly.
Scotland’s next game is against hosts Portugal tomorrow and another win would secure at least second place and qualification for the second round in the new year.
Meanwhile, in Dublin, Scotland’s women lost 3-2 to South Africa in a training game prior to the FIH Champions Challenge.
The Scots led 2-1 at one stage through goals by Vikki Bunce and Nikki Lloyd but the South Africans, who play the Scots in the final pool match next Tuesday, hit back.