Gary Pigree, the impressive French Guyana forward, netted his eighth goal in seven Caribbean Cup games to open the scoring. A splendid solo run by Jean-Claude Darcheville unbalanced the Jamaican defense. Rather than take the shot himself, the former Rangers and Bordeaux star unselfishly located Pigree advancing from the right.
The 24-year-old appeared to have mistimed his attempt, but Jamaican goalkeeper Dwayne Miller failed to collect cleanly and the ball rolled into the net, giving the upstart a 19th minute 1-0 lead.
But that joy was short lived as Jamaica's Tramaine Stewart tore down the right flank into the 18-yard box and, without hesitation, hammered a shot past helpless goalkeeper Laurent Pecthy to level the score just three minutes later.
The Reggae Boyz came out for the second half in a spirited mood, but it was French Guyana that got the goal.
In the 48th minute, the 37-year-old Darcheville threaded another precise pass, this time to Rudy Evans, who tallied to give French Guyana a 2-1 advantage that it would never relinquish.
Jamaica had a chance to salvage a point with 10 minutes remaining, but Pecthy demonstrated his class and sealed a win for his side by saving back-to-back efforts from Darren Mattocks and Demar Phillips.
Group B play continues on Monday with another doubleheader. French Guyana will face Cuba in the opener, followed by a meeting between Jamaica and Martinique.