Abstract: Objective To explore the expression and clinical significance of programmed cell death ligand-1（PD-L1） in head and neck tumors. Methods From January 2015 to June 2016， surgical specimens of 40 cases of head and neck malignant tumors and 20 cases of head and neck cyst tissues were prepared by embedding into paraffin blocks. The expression of PD-L1 protein was detected by immunohistochemistry SP two step method. The relationship between PD-L1 expression and clinical pathological parameters（age， sex and pathological grade and clinical stage） was investigated. Results PD-L1 was not expressed in head and neck cyst tissues， and the positive rate was 65.0%（26/40） in head and neck tumor tissues， significantly higher than that in head and neck cyst tissues（P<0.05）. The expression of PD-L1 was not associated with age， sex and pathological grade（P>0.05）， but was related to clinical stage（P<0.05）. Conclusion The expression of PD-L1 was significantly increased in head and neck malignant tumors，which could provide a reference for the immunotherapy of head and neck malignant tumors.