The purpose of the research is to assess the internal factors affecting to the human resource management of Hai Duong clean water business joint stock company. This study employs samples based Primary data were collected through a structured questionnaire in 2021. To carry out the research objectives, the authors conducted quantitative analysis through the Correlation analysis and OLS multivariable regression. The results shown that the internal factors (Organizations Size, Organizational Structure, Business Strategy, Organization Culture, Senior and Middle Management, Training and developing human resources, and Employee’s attitude) are positively affect to human management; Empirical research results show that the factors that have a positive and strong impact on human resource management (HRM) are Organization Culture, Senior and Middle Management and Training and developing human resource. In addition, factors with a positive impact but weaker effect include Organizations Size, Organizational Structure, Business Strategy. The findings of this study suggest that when Hai Duong Clean Water Joint Stock Company develop strategies and policies on human resources, it is necessary to consider this internal factor effectively.