Abstract：Objective To analyze the occlusal support status of posterior teeth，and to clarify the impact of severe tooth attrition on the restoration of aged teeth. Methods A total of 82 elderly patients with severe tooth attrition，who underwent occlusal reconstruction and restoration at our hospital from August 2020 to August 2021 were selected. According to the degree of posterior occlusal support，they were randomly divided into a study group and a reference group, with 41 cases in each group.The changes in the chewing cycle, activity-to-rest ratio, and electromyographic（EMG） integral values of bilateral masticatory muscles（MM）, anterior temporal muscles（TA）, and posterior temporal muscles（TP） at different periods （pre-restoration，transitional period，and 1 month after permanent restoration）were compared between the two groups. Results There were no statistically significant differences in the chewing cycle indicators between the two groups before restoration（t＝1.717, －0.006, －1.060, all P＞0.05）. The MM, TA, and TP chewing cycle levels during the transitional period were higher in the study group than in the reference group, while the MM, TA, and TP levels 1 month after permanent restoration were lower in the study group（t＝－6.596,－7.666,－8.248, 4.447, 4.095, 3.986, all P＜0.001）. The activity-to-rest ratio of MM, TA, and TP chewing movements before restoration, during the transitional period, and 1 month after permanent restoration was lower in the study group compared to the reference group（t＝3.836, 4.048, 5.231, 34.577, 18.036, 12.501, 8.880, 6.251, 4.765, all P＜0.001）. The EMG integral values of MM, TA, and TP chewing movements before restoration and during the transitional period were higher in the study group compared to the reference group（t＝－12.868, －9.252, －11.981, －4.012, －6.677, －9.022, all P＜0.001）. One month after permanent restoration, the MM and TA scores were lower in the study group, while the TP score was higher compared to the reference group（t＝7.885, 4.511,－3.770, all P＜0.001）.  Conclusion The state of posterior occlusal support significantly affects the outcomes of occlusal reconstruction in elderly patients with severe tooth wear.