Best human resource management practice is composed of a series of interrelated and mutually promoting human resource management practices, can significantly improve the performance of an organization by matching with its specific strategic environment. The Chinese international hydraulic engineering enterprises, which involve employees from different countries, need to pay attention to the international management characteristics. Therefore, this paper used single-case qualitative research methods, on the basis of traditional best human resource management practice research, combined with the specific management situation in the process of Chinese water international engineering enterprises, from the perspective of contingency and resource theory of strategic human resource management theory, deeply explores best international human resource management practice of Chinese water international engineering enterprises in the context of ‘Belt and Road Initiative’. The main factors of best international humen resource management practice including localized recruitment and international talent team selection, cross-cultural training and international talent cultivation for “profession”, the comprehensive assessment system and a complete and fair promotion path for “placement” practice, competitive overseas salary levels, “preservation” practices that meet the needs of employees at all levels. This paper also clarified the mechanism of the impact of various international human resource management practices on Chinese water international engineering enterprises performance based on the AMO model.