How to evaluate economic linkage effect of high-tech industry is the key to the development of high-tech industry.The evaluation index system of economic linkage effect of leading high-tech industry which is based on technical innovation dimension, industrial linkage effect dimension, economic benefit and social benefit dimension, can evaluate this linkage effect of different hightech industries. Judging from the evaluation, the development of leading high-tech industry can be properly considered, which range from electronics and communications equipment manufacturing, pharmaceutical manufacturing, medical equipment and instruments manufacturing, to electronic computer and office equipment manufacturing, aviation aircraft manufacturing. Meanwhile, studies on the formation process of high-tech industry suggest that the demand of the country, the industrial innovation and economic linkage effect are the essential elements. The main influential factors of formation process existing in the industrial innovation process include the policy system, the market system and the technology system. The paper concludes that more attention should be paid to institutional innovation, organization innovation and technology innovation in the development of leading high-tech industry.