Abstract: Paraffin-based phase-change-material mixed clay (PCM-clay) provides a new solution to solve the problem of anti-freezing and temperature control during the construction of clay core wall in cold regions in winter. However, the phase change of PCM with different crystallinity at different temperatures leads to different compaction properties of PCM-clay. The control standards of compaction parameters of PCM-clay with different PCM crystallinity need to be further studied. Considering that field rolling tests not only have high costs, but also make it difficult to control the test temperature of PCM to reach the set crystallinity in a variable environment, the PFC 3D software is used to establish the rolling discrete element model of phase change clay under different PCM crystallinity according to the similarity rate of roller and load simulation. The validity of the discrete element model is verified by the indoor compaction test results. The influence of different rolling parameters on the compaction quality of PCM-clay is analyzed, and then the recommended rolling parameters of PCM-clay under different PCM contents and different PCM crystallinity are given. The results show that when the vibratory force is too small, it is difficult to achieve the compaction effect of large vibratory force even if the number of rolling passes is increased. Properly increasing the vibratory force is beneficial to compaction. The increase of the crystallinity of PCM will reduce the dry density of PCM-clay. By increasing the number of rolling passes, reducing the rolling speed and appropriately reducing the paving thickness, the compaction effect of the phase change clay can be improved to achieve the maximum dry density when the PCM is not crystallized. This study can provide a new method for analyzing the compaction quality of PCM-clay at different construction temperatures, and also provide a theoretical basis for the compaction quality control of PCM-clay in core wall with different PCM crystallinity.