Abstract
Recent results of a high-statistics τ lepton studies at B factories are reported. Reviewed are the measurements of Michel parameters in leptonic and radiative leptonic τ decays at Belle, as well as the measurement of the branching fractions of the radiative leptonic τ decays at BABAR. Searches for CP symmetry violation in hadronic decays with $ \mathop K\nolimits_S^0 $ are also briefly discussed.