Supersymmetric corrections to $\varepsilon$'/$\varepsilon$ at the leading order in QCD and QED

We study the corrections to \epsilon^\prime /\epsilon in the minimal supersymmetric model at the leading order in QCD and QED. Supersymmetry can increase the standard model prediction for \epsilon^\prime /\epsilon by at most 40\% for m_t=174 GeV, an enhancement which is indistinguishable from the present theoretical uncertainties. The most conspicuous effect of supersymmetry is a strong depletion of \epsilon^\prime /\epsilon. For certain choices of supersymmetric parameters, vanishing and even small negative values of \epsilon^\prime /\epsilon can be obtained for the top quark in the CDF range.