He has been beaten on a 3-2 split decision against Indonesia's Aldoms Suquor in the last 64.
Earlier this year he secured a bronze medal at the European Games.
He beat Spain's Martin Molina Salvador on a split decidion in their light-flyweight boxing quarter-final in Minsk.
Buckley then advanced to the semi-finals but lost out along with Michael Nevin and Grainne Walsh.
The Wicklow native won Ireland's first medal at this Games.