Abstract: In order to explore the externalities of R&D activities and accurately measure their spillover effect, based on the nature of the spillover effect of R&D activities and combined with Leontief′s coefficient of complete consumption, the concept of complete spillover effect is proposed and the spillover effect matrix and measure model of R&D activities are constructed on the micro level of  enterprise according to the feature of the spillover effect Based on this, the spillover effect of the listed companies in the electrical machinery and equipment manufacturing industry from 2009 to 2015 is analyzed Results show that spillover effect exists in R&D activities and is represented in the form of complete spillover effect, and the spillover capability of an enterprise is an important part of the innovative ability of the enterprise The above conclusions can provide a theoretical basis for the government to optimize the flow of research funding and dynamically adjust the R&D investment structure

Key words:  R&D activities, complete spillover effect, innovation ability, measurement