Abstract: OBJECTIVE To assess the human resource allocation needs and workload changes of the Hospital-associated Infection Management Department of a tertiary hospital between 2021 (during the pandemic) and 2024 (post-pandemic) with the Workload Indicators of Staffing Need (WISN) recommended by the World Health Organization (WHO). METHODS Workload data of the Hospital-associated Infection Management Department of Nanjing Gaochun People's Hospital in 2021 and 2024 were collected.Strictly following the standard steps of the WISN method， the workload was systematically quantified and converted into specific human resource needs.The WISN ratio， staffing needs and time allocation for various work compositions were calculated and compared between the two years. RESULTS The study showed that with the same staffing of six individuals， the theoretical need based on workload was 7 individuals in 2021， and the WISN ratio was 0.86， indicating insufficient personnel.In 2024， the theoretical need for WISN was 5 individuals， and the ratio rises was 1.2， indicating sufficient personnel. Infection control activities were the main source of workload， and the proportion of supportive and additional activities (such as training， meetings，etc.) changed significantly over time. The Career Adjustment Factor (CAF) decreased from 1.94 in 2021 to 1.70 in 2024， and the Individual Adjustment Factor (IAF) decreased from 0.60 to 0.45， reflecting the simplification of work structures and reduction of emergency tasks after the pandemic. CONCLUSIONS The human resource allocation of the Hospital-associated Infection Management Department should be based on dynamic and precise workload assessments， rather than a single bed-to-staff ratio. The WISN method can effectively quantify workload and convert it into specific human resource need indicators， providing a reliable basis for medical institutions to achieve scientific and refined allocation of human resources.