This study assimilated IT and HR literatures to investigate the relationships between IT competencies, HR competencies, and job performance for HR professionals. Drawing on a sample of 122 HR professionals from 8 financial service companies in Taiwan, our results show that IT competencies and HR competencies are positively and significantly associated with job performance, and HR competencies partially mediate the relationship between IT competencies and job performance at the individual level. Further, the study also support for IT competencies as a determinant of HR competencies and job performance. The theoretical and managerial implications and contributions of these findings are discussed.