The present application relates to a negative electrode material for a secondary battery. The negative electrode material includes an expanded graphite and an organic phase change material intercalated into the expanded graphite. The present application further relates to a method for preparing the negative electrode material and a secondary battery using the negative electrode material. Since the organic phase change material is intercalated into the expanded graphite, when an internal temperature of the secondary battery increases, the organic phase change material absorbs heat by phase change, which can improve the heat storage and energy storage capacity and the safety performance of the secondary battery. In addition, since the organic phase change material has certain viscosity and flexibility, the adhesion performance of the negative electrode material on the current collector can also be improved.