Recent influential literature argued that international trade promoted knowledge flows and technology diffusion between trading partners.Specially,knowledge produced through R&D in developed countries would spill over through trade to other countries.This paper introduces a factor of actual imports penetration rate in the measuring model of technology spillovers on the basis of previous literature and explores the extent to technology diffusion through imports in China.The empirical study of China shows that the advanced technology and R&D achievement of trade partners significantly promote China's technology progress through imports.And domestic R&D investment is more important than foreign country's to TFP.