Objective. The purpose of this paper is to confirm the core competencies required for middle to senior level managers in Victorian public hospitals in both metropolitan and regional/rural areas. Methods. This exploratory mixed-methods study used a three-step approach which included position description content analysis, focus group discussions and online competency verification and identification survey. Results. The study validated a number of key tasks required for senior and middle level hospital managers (levels II, III and IV) and identified and confirmed the essential competencies for completing these key tasks effectively. As a result, six core competencies have been confirmed as common to the II, III and IV management levels in both the Melbourne metropolitan and regional/rural areas. Conclusions. Six core competencies are required for middle to senior level managers in public hospitals which provide guidance to the further development of the competency-based educational approach for training the current management workforce and preparing future health service managers. With the detailed descriptions of the six core competencies, healthcare organisations and training institutions will be able to assess the competency gaps and managerial training needs of current health service managers and develop training programs accordingly. What is known about the topic? A competent health service management workforce is critical to the effective functioning of the healthcare system. Consequently, a competency-based educational approach has been proposed to prepare current and future health professionals including health service managers. Although the literature has suggested that core competencies exist for different management levels in different healthcare settings, there has been no study which has provided valuable data to indicate what the core competencies are for hospitals managers in Australian public hospitals. What does this paper add? This paper identified and confirmed that six core competencies are common to middle to senior level managers (levels II-IV) in Victorian public hospitals in both Melbourne metropolitan and regional/rural areas. What are the implications for practitioners? The findings of the study is the first step towards supporting the competency-based educational approach for training and preparing current and future health service managers for their roles. The six identified core competencies provide a very useful guide to the identification of competency gaps and managerial training needs, and the further development of the health service management training curriculum.