Gauge Coupling Unification has been studied in a class of weakly coupled heterotic string models compactified on an anisotropic orbifold. Light (~ 10^13 GeV ) exotic particles were required for the gauge couplings to unify at the string scale. We consider the scenario when the exotics of the string model act as messengers of Gauge-Mediated SUSY breaking and calculate the low energy spectrum. We find that the spectrum of the gauginos in these models depend on the threshold corrections at the Grand Unification scale. We also find that a light gluino ensures precision unification of the couplings.