Spatial evaluation of knowledge spillover benefits in China’s free trade zone provinces and cities

China has established several free trade zones (FTZs) in recent years, which are becoming new drivers of growth for regional economic development. As the FTZ reform deepens, protecting intellectual property rights and improving application systems have become important for encouraging innovation in FTZs. To understand the knowledge spillover effects in different FTZs, this paper selects indicators at different levels of knowledge evaluation and uses the 2017 data of the provinces and cities where the first three batches of FTZs set up by China are located as samples to perform empirical analysis on knowledge spillover effects with a corrected spatial knowledge spillover model. According to the evaluation, the spatial knowledge spillover effects vary among FTZs—the spatial knowledge spillover effects of economically developed regions are smaller (0.0421), while their spillover effects on other FTZs are bigger (0.0795). In addition, the knowledge spillover effects of adjacent FTZ provinces and cities are significantly greater; the spatial spillover effects of southeastern coastal FTZ provinces and cities are more than those of central and western regions as well as northeastern provinces and cities (0.0795; 0.0533; 0.0672). This study is helpful for governments and policy makers to develop appropriate incentive policies for knowledge innovation targeting the knowledge spillover characteristics of different FTZs.