Objective To explore the possible mechanism of spindle and centromere associated complex subunit 3 ( SKA3 ) in regulating the malignant biology of oral squamous cell carcinoma ( OSCC ). Methods Expression levels of SKA3 in oral squamous cell carcinoma (n= 25) and adjacent tissues (n= 15) were detected by immunohistochemistry. The proliferation of CAL27 cells was assessed using a cell counting kit-8 assay,while migration and invasion were evaluated via scratch wound and Transwell assays, respectively. Expression levels of SKA3, protein tyrosine phosphatase non-receptor type 14 (Ptpn14), and Yes-associated protein-1 (YAP1) were detected by Western blot, and p53-binding protein 1 ( 53BP1) and the histone variant γH2AX were detected by immunofluorescence. The cell cycle and apoptosis rate were measured by flow cytometry. Results SKA3 expression levels were higher in clinical OSCC than in normal oral mucosal tissue samples(P<0. 01). Silencing SKA3 increased Ptpn14(P<0. 01) and inhibited YAP1 protein in cell experiments(P<0. 05), while overexpression of SKA3 had the opposite effects(P<0. 01). Silencing SKA3 also reduced the proliferation, migration, and invasion of OSCC cells(P<0. 01), blocked the G2/ M phase of the cell cycle(P<0. 01), and promoted DNA damage and cell apoptosis(P<0. 01) in CAL27 cells, while the YAP agonist XMU-MP-1 reversed the effect of silencing SKA3 ( P<0. 05, P<0. 01). Conclusions Silencing SKA3 inhibits YAP1 protein expression by activating the Hippo / YAP signaling pathway, thereby inhibiting the proliferation, migration, and invasion of OSCC cells, and promoting DNA damage and cell apoptosis.