Quantitative evaluation of the effect of tax policies is of great practical significance for giving play to the structural adjustment advantages of fiscal and tax policies and strengthening the coordination between different macro-control measures. This paper takes the announcement [2016] No. 42 of the State Administration of Taxation in China as a quasi-natural experiment to study how anti-avoidance policies affect the investment level of multinational enterprises. The research finds that: (1) compared with non-multinational enterprises, multinational enterprises have significantly reduced their investment level after the promulgation of the Anti-tax-avoidance provisions; (2) The mechanism analysis shows that after the policy was issued, the tax burden, financing constraints and internal governance level of the experimental group enterprises have been improved, and the change of enterprise investment level stems from the impact of anti-avoidance policies on the above aspects of enterprises to varying degrees. Under the joint action of different mechanisms, the Anti-tax-avoidance provisions has reduced the level of enterprise investment. The conclusion of this paper provides a basis and reference for the improvement of the subsequent Anti-tax-avoidance provisions.