  Cosmological baryon asymmetry B is studied in supersymmetric standard models,
assuming the electroweak reprocessing of B and L. Only when the soft
supersymmetry breaking is taken into account, B is proportional to the
primordial B-L in the supersymmetric standard models. The ratio $B/(B-L)$ is
found to be about one percent less than the nonsupersymmetric case. Even if the
primordial B-L vanishes, scalar-leptons can be more efficient than leptons to
generate B provided that mixing angles $\th$ among scalar leptons satisfy
$|\th| < 10^{-8} (T/{GeV})^{1/2}$.
