The phase change process is of significant importance in the application of phase change material (PCM). In this paper, the modified enthalpy-transforming lattice Boltmznan (LB) model is developed to trace the location of solid-liquid interface, using the polynomial enthalpy function. The problems of two-region phase change and phase change by convection are solved to evaluate the presented LB model. The results show that by removing the non-differentiability of linear and hyperbolic-tangent enthalpy functions, the LB model with polynomial scheme can get the temperature distribution more accurately in the problem two-region phase change. Besides, in the problem of phase change by convection, resulted from the variable equivalent heat capacity during phase change, the melting rate of polynomial scheme is between linear scheme and hyperbolic-tangent scheme. (C) 2019 Elsevier Ltd. All rights reserved.