Background: To evaluate the expression status of ARHI protein and pRb2/p130 in endometrial cancer (EC), while analyzing the relevance in EC simultaneously. Materials and Methods: Surgical resection of 20 tumor samples from primary EC patients, 20 atypical hyperplasia endometrial samples, and ten normal endometrial samples from benign disease such as uterine fibroid after surgery were randomly chosen for co-immunoprecipitation assays, which was used to explore the expression of ARHI and p130. Results: The positive status of ARHI protein in dropped gradually from normal endometrial tissues at proliferative stage (90%), endometrial tissues of atypical hyperplasia (50%) to EC tissues (30%); statistically significant differences were evaluated among the groups (p < 0.05). Meanwhile The positive rate of pRb2/p130 decreased gradually, which had a apparent difference among groups (p < 0.05). There were correlations between lack of positive statue of ARHI and the degree of EC and clinicopathological classification (p < 0.05). However the positive expression statue of ARHI protein was not associated with the histological type (p > 0.05). However, there were correlations between lack of positive expression of pRb2/p130 and the degree of EC, classification of surgical pathology, and histological type (p < 0.05). Conclusions: The drop or lack of the positive expression status of ARHI protein and pRb2/P130 result in the occurrence and worsening of EC.