Objective To assess the current knowledge and skills of pediatric intensive care unit (PICU) nurses in pain assessment and to identify the influencing factors, so as to provide a reference for improving the quality of pain management. Methods A conve-nience sample of 299 PICU nurses was recruited from seven hospitals across Eastern, Southern, Central, Northwestern, and Northeastern China. Data were collected using a general information questionnaire, a pain assessment knowledge test, and 10 standard case scenarios. Results The mean score of pain assessment knowledge test was 35.06±11.68, with an overall correct rate of 35.1%. The median score of standard cases was 3 (2, 4), with an overall correct rate of 32.3%. Multivariate analysis identified educational background and geographic region as significant factors influencing knowledge levels (both P＜0.05). Furthermore, geographic region and knowledge level were significant factors influencing clinical skills in pain assessment (both P＜0.05). Conclusion The knowledge and skills of PICU nurses in pain assessment are relatively poor. Targeted training and cross-regional resource sharing are recommended to continuously enhance pain management competencies of PICU nurses.