This study examines the extent to which existing foreign direct investment (FDI) theories apply to Chinese investment in the Belt and Road Initiative (BRI) countries. This is important because existing explanations of Chinese outward FDI (OFDI) generally make scant reference to these theories. By using OFDI data for BRI countries between 2003 and 2017, we tested hypothesizes applicable to existing theories by using both pooled ordinary least squares (PLOS) and stochastic frontier analysis (SFA) methods. The results show that a large part of the existing theories apply to Chinese OFDI. Chinese OFDI is likely to choose countries with big market size, abundant natural resources, cheap unskilled labor, stable politics, good infrastructure, high trade cost and high investment cost. These positive findings notwithstanding, they do not invalidate the alternative factors cited by commentators which have not been subject to direct testing, which may require the use of qualitative analytical approaches.