Objective To evaluate the expression of YAP protein and epithelial mesenchymal transition (EMT) associated proteins E cadherin and Vimentin in cervical squamous cell carcinoma and its clinical significance. Methods Expression level of YAP protein and EMT associated proteins E cadherin and Vimentin proteins in cervical carcinoma were detected by imm uno his tochemical method in 20 normal cervix, 50 cases SIL and 125 cases cervical squamous cell carcinoma. The relation with clinical pathologic parameters was analyzed. Results The positive expression rate of YAP, E cadherin and Vimentin were 71. 20%, 55. 20% and 48. 80%, Compared with SIL and normal cervical tissue (P<0. 05). YAP expression was significant correlation with the degree of histological grade and lymph node metastasis (P<0. 05) , E cadherin and Vimentin expression were significant correlation with the degree of histological grade, FIGO stage and lymph node metastasis (P<0. 05) , but there was not obviously correlated with other clinical pathological parameters (P>0. 05). YAP expression was negative correlated with E cadherin (r=-0. 395 , P<0. 05) , YAP expression was pos itive correlated with Vimentin (r=0. 338, P<0. 05). Conclusion The expression of YAP protein may be related to the occurrence and development of cervical squamous cell carcinoma, and may promote the invasion and metastasis of cervical squamous cell carcinoma by regulating EMT.