Homogeneous nucleation of liquid droplets in superheated crystals is considered in order to estimate the maximum superheating of crystals. Using the previously derived universal order parameter model of the crystal-melt transition (Iwamatsu M and Horii K 1996 J. Phys. Soc. Japan 65 2311), it is determined that the catastrophic homogeneous nucleation occurs at , where is the equilibrium melting point. This numerical estimation is consistent with the results of maximum-superheating experiments.