Abstract The polarization of τ leptons in the reaction e+e− → τ+τ− has been measured using a e+e− collider, TRISTAN, at the center-of-mass energy of 58 GeV. From the kinematical distributions of daughter particles in τ → eν ν , μν ν , ϱν or π(K)ν decays, the average polarization of τ− and its forward-backward asymmetry have been evaluated to be 0.012±0.058 and 0.029±0.057, respectively.
