In a competitive business environment, many companies struggle to align their resources to improve their performance. The resources should become one of the company's competitive advantage. One of those competitive advantages is knowledge assets. Knowledge assets can be developed by optimizing human resource management because not all companies want to invest funds to develop a knowledge management system. Initiation of knowledge sharing behavior among workforces is considered to be one of the most efficient ways. In Indonesia, it is predicted that 46% of workforces in 2020 are millennials. Many previous studies have looked at millennial behavior in the work environment, and they are considered to potentially inhibit the development of the company's knowledge assets due to a high turnover rate. This paper is aimed to explore the factors that promote or discourage knowledge sharing behavior of millennials workforce. Factors studied included psychological, organizational culture, cognitive abilities, technological facilities, and so forth. The PLS method is used to explore these factors. A strategy has been developed as a recommendation for companies to initiate a knowledge sharing culture.