Irish captain Egan, Sutherland and Joyce qualified automatically for the 2008 Olympics courtesy of their semi final wins at the final Olympic qualifier for European boxers in the Greek capital yesterday.
And the Beijing bound trio followed that up with three gold medals wins at the Olympic Centre of Nikaia.
Light welterweight Joyce, of the Michael’s Athy club, finished on top of the podium after his opponent, Egidijus Kavaliauskas of Lithuania, retired injured in the first round with the scores tied at 2-2.
And St Saviours Dublin middleweight Sutherland won gold after his opponent, Jean-Michael Raymond of France, retired in the second round. Sutherland was 8-2 up.
Swedish light heavyweight Kennedy Katende went the distance with Egan, but the Dubliner ensured the hat-trick after earning a 15-10 win.
The final placings for the nations competing in Athens will be decided shortly and Ireland looks set for at least a top two finish based on points awarded for victories.
Twenty five Olympic places will have been distributed once the semi final box-offs are completed later today.
Light flyweight Paddy Barnes and bantamweight John Joe Nevin qualified for the 2008 Olympics before Athens.
The Irish squad are due to arrive home via Dublin Airport at midnight on Sunday.