The solid-liquid phase change of paraffin wax and other materials stores and releases heat through phase change. The melting and solidification process occurs mainly in the mushy zone where solid and liquid coexist. The study of the motion and heat transfer characteristics of particles within the mushy zone is important to grasp the basic mechanism of solid-liquid phase change. In this paper, the theoretical analysis and numerical simulation are used to study the phase change and heat transfer characteristics in the motion of particles. The mathematical model of phase change and heat transfer during particle motion is established by tracking the migration and deformation of the particle with the arbitrary Lagrangian-Eulerian (ALE) method. Three-dimensional finite element method is used to simulate the motion of spheric particle and to analyze the heat and mass transfer phenomena during particle motion. The velocity field, solid phase rate and temperature field changes during the particle motion are obtained to describe the flow and heat transfer characteristics of the particle motion of the phase change process. The results show that the particles fall vertically along the center of the channel. The particle surface is subjected to inhomogeneous temperature and velocity fields, which results in the particle forming a shape with a pointed front end and a rounded tail.