[Purpose/significance]Intelligence agency and think tank are both closely related to strategic decision. Due to special condition of China, Chinese intelligence agency and think tank have overlapping functions，researching on this topic will help to further clarify the difference and connection between intelligence and think tank functions. [Method/process]From the perspective of intelligence classification, this paper analyzes characteristics of different types of intelligence agencies. It also studies the relevance between intelligence agency and think tank in the big data era, and discusses the effective interaction among intelligence, think tank and strategic decision. [Result/conclusion] Research shows that the decision-making chain the "data information collection-intelligence analysis-countermeasure research-decision-making" , the second and third links in the past were mainly divided into domestic and foreign countries, but now they are more based on work areas and work，the nature of the distinction, so the intersection of intelligence products and think tank work increases.