Abstract: The efficiency evaluation of technology innovation is aimed to measure the output of technology, efficiency of resource utilization centered on enterprise and find out important factors of technology innovation efficiency. The enterprise is the main part of technology input and output in this research. Data Envelopment Analysis is used to do empirical analysis of 15 sub-provincial cities in China. The pure technology efficiency and scale efficiency is measured to determine the scale is big or small. By screening the important factors that signally influence technology efficiency, the key problem of every sub-provincial city is find out. The innovations and characters: firstly, in this paper the efficiency evaluation model included all indicators is the basic model and the efficiency evaluation model without one indicator X_i is the comparison model. By t test, it is verified if the efficiency difference between basic model and comparison model is significant. If the difference is significant, the indicator X_i is the key factor. It changes the existing research can't screen the key indicators by DEA. Secondly, empirical result shows that the key indicators include "R&D expenses of industrial enterprises above designated size" "financial funds to technology" "technology professionals" "new products output of industrial enterprises above designated size" "technical market turnover". Thirdly, empirical results show that the reasons why technology efficiency is low for different sub-provincial cities are different.

Key words: technology innovation, technology efficiency, DEA, t test, key indicators