Implementation of Enterprise Resource Planning systems (ERPs) is a complex and costly process which usually results in serious risks. The majority of previous research projects have been conducted in identifying ERP Critical Success Factors (CSFs) in order to identify the main factors enhance success achievement. Project managers' skills of ERP system implementation projects as one of such facilitating factors, are not well studied and its different aspects are discussed in the extant literature. With this in mind, this research aims at studying and identifying the most related project managers' skills of ERP system implementation projects which proposes a classification scheme along with a ranking model. The paper, based on the results of the Exploratory Factor Analysis (EFA) categorizes 18 identified skills into four distinct groups of managerial, project management, human resource and technical. The results of this study have provided a very useful reference for scholars and managers to identify the relevant issues of ERP implementation projects managers' skills.