The sudden outbreak of COVID-19 in 2019 brought serious risks and challenges to the R&D input and output of industrial enterprises on the scale. It is of certain theoretical significance to propose solutions and countermeasures and reasonably plan the R&D input and output.Based on the analysis of the R&D input-output situation of industrial enterprises before and after the outbreak of COVID-19, a model was established with the output rate, export rate, technical efficiency and effective technical efficiency of new products in R&D activities of industrial enterprises as explanatory variables, and the R&D activities of enterprises as control variables. The improved knowledge production function was used to construct the model. SPSS26 software was used for regression analysis to study the spillover effect of R&D input and output. The results show that output rate and export rate of new product in the R&D, technical efficiency and effective technical efficiency of industrial enterprises before and after the outbreak of the COVID-19 epidemic have different impact on the spillover effect. Different modifiers exhibited different levels of significance. Among them, the export rate of new products has a significant impactat the 5% level. after the outbreak of the epidemic.