With the intensification of global competition and development of investment theories, foreign direct investment (FDI) is no longer solely affected by economic factors. Many noneconomic factors, such as policies and institution, now play an important role in FDI inflow. As a composite indicator, business environment has attracted a growing attention from investors. From theoretical and empirical perspectives, this paper quantifies and qualifies the influence of business environment over the FDI under different conditions. The impact mechanism of business environment on the FDI was refined by decomposing business environment into multiple subfactors, and considering various factors of different economies, such as natural resources (NR), technological resources (TR), and political stability (PS). An empirical analysis was conducted on the panel data of 26 countries in 2005-2018. The results show that: the host country can attract more FDI inflow by improving business environment, NR, TR, and PS; excessively high NR and TR, to a certain extent, suppress the promotion effect of business environment on FDI; four subfactors of business environment, namely, the protection of small and medium investor (PI), cross-border trade (CT), electricity supply (ES), and insolvency (IN), have relatively high promotion effects on FDI inflow. The research results enrich the theories on FDI and business environment, and provide a reference for the design of innovative polices.