This paper established an efficiency evaluation index system of input and output on science and technology innovation. In order to decrease the influences of uncertain factors for the experimental results and increase the accuracy of the results,the researcher calculated the efficiency of science and technology innovation from 2011 to 2015 in 18 cities of Henan province by using the grey DEA model which was combined the grey theory with DEA model in this paper. The results showed that in the cities of Henan...