OBJECTIVES: The purpose of this study is to examine the determinants that influence the level of core competencies of IPCPs in different hospitals in Guizhou in Southwest China. METHODS: This study conducted a cross-sectional survey of IPCPs from April to June 2022, using a competency self-assessment scale for IPCPs that encompassed 4 core dimensions, 11 sub-dimensions and 47 measurement items. RESULTS: The self-assessment competency score of 1083 IPCPs from 511 hospitals was 4.891±1.204. Among the four core dimensions, the lowest self-assessment score was for professional development ability at 4.494±1.291, and among the 11 sub-dimensions, the lowest score was for comprehensive knowledge at 3.748±1.578. The core competencies of different hospitals showed that traditional Chinese medicine hospitals had the highest score of 5.306±1.071. Linear regression analysis showed that the independent factors influencing self-assessment competence were age(B=0.487, 95%CI:0.189-0.785), years of IPC practical experience(B=0.216, 95%CI:0.050-0.382), professional title(B=-0.395, 95%CI:-0.693--0.097), monthly income(B=-0.296, 95%CI:-0.484--0.107), experience in frontline epidemic response(B=0.236, 95%CI:0.098-0.382), proficiency in office software applications(B=-0.747, 95%CI:-0.898--0.596) and cultural atmosphere of hospital IPC(B=-0.406, 95%CI:-0.799--0.013). CONCLUSIONS: The core competencies of IPCPs in China require enhancement. Differences in the core competencies of IPCPs in different hospitals were identified, providing substantial evidence for the further development of competency-based training programmes.