The “Belt and Road” initiative is a booster for accelerating domestic reforms and opening to the outside world, which has a major impact on the sustainable development of the Chinese economy and corporate investment and financing decisions. This article cuts in from a new perspective of cash holding level, and uses the quasi-natural experiment provided by the “Belt and Road” initiative to test its microeconomic effects. In theory, the implementation of the “Belt and Road” initiative will increase the operational and financial risks faced by enterprises, and cash is an important tool for enterprises to resist risks. Therefore, companies may increase their cash holdings to resist risks. An empirical test using Chinese A-share listed companies from 2011 to 2017 as a sample supports the above theoretical expectations. The study found that the implementation of the “Belt and Road” initiative has increased the level of cash holdings of enterprises, that is, the cash holdings of participating enterprises of the “Belt and Road” initiative have increased significantly, and this increase was mainly achieved by increasing the company，s operating and financial risks. Further analysis shows that the “Belt and Road” initiative，s role in improving the cash holdings of participating companies is even more pronounced in companies that are not audited by ‘big 4’ firms and have relatively low independent directors. At the same time, this paper finds that the improvement of cash holding level of participating enterprises mainly comes from external borrowing and asset disposal. This paper expands the research on the economic consequences of the implementation of the “Belt and Road” initiative and enriches the analysis of the influencing factors of corporate cash holdings.