随着社会经济的发展，技术创新受到高度重视。企业是经济活动的重要参与者，企业的创新水平影响着全社会技术创新的发展。董事会是现代企业的重要组成部分，是公司的最高决策层，在企业创新活动中发挥着关键作用。因此研究董事会对于企业创新的影响具有现实意义。 董事会资本包括人力资本、社会资本两方面，衡量董事会成员为企业提供资源的能力；企业创新可分为创新投入、创新产出两部分。已有研究多集中于董事会资本对创新投入的影响，本文建立了“董事会资本—研发投入—创新产出”的研究框架，就董事会资本与研发投入、董事会资本与创新产出、研发投入的中介作用进行研究，以更好地了解董事会资本作用于企业创新的机制。 本文以2015年A股1076家上市公司为研究对象，以技术背景、教育背景、政治背景、连锁任职四个变量反映董事会资本，以研发投入强度反映创新投入，以发明专利授权数反映专利产出，并根据研究框架，借鉴前人中介效应研究方法建立三步回归模型进行实证研究。研究发现，董事会人力资本，即董事技术背景、教育背景对企业研发投入有正向影响，董事会社会资本中的连锁任职对研发投入有正向影响；技术背景、教育背景有利于企业的创新产出，且其不仅直接作用于创新产出，还通过研发投入产生间接影响。 针对董事特征与研发投入之间互为因果的内生性问题，本文通过引入董事会资本的行省份-行业均值工具变量的方法进行处理，得到了一致的结果，验证了结论的可靠性。 基于本文研究结论及现实背景，本文提出以下建议：政府完善相关政策，引导有相关技术经验、教育背景良好的人才资源流向企业，充分发挥董事为企业提供资源的作用；企业重视人力资本在企业创新中的重要作用，并积极利用连锁任职网络资源优势，获取信息、关系资源，推动创新投入决策，并促进创新投入向创新产出的转化。

With the development of social economy, technological innovation is highly valued. Enterprises are important participants in economic activities, and the level of innovation of enterprises affects the development of technological innovation in the whole society. The board of directors is an important part of modern enterprises, and is the highest decision-making level of the company, playing a key role in corporate innovation activities. Therefore, it is of practical significance to study the impact of the board of directors on corporate innovation. The board capital includes human capital and social capital. It measures the ability of board members to provide resources for enterprises. Enterprise innovation falls into innovation input and output. Most of the existing researches focus on the influence of board capital on innovation input. This paper establishes the research framework of Board Capital – R&D Investment – Innovation Output, which studies the mediating role of R&D, to better understand the mechanism of board capital acting on enterprise innovation. This paper takes 1076 listed companies in A-shares in2015 as the research object. Technical background, academic background, political background and interlocks are used as proxies for board capital, R&D intensity is used as proxy for innovation input, and the number of grants of invention patent is used to reflects innovation output. A three-step regression model based on the research method of mediating effects is set. The study found that the human capital of the board, that is, the technical background and education background of the directors have a positive impact on the R&D. The interlock in the social capital has a positive impact on the R&D; the technical background and academic background are conducive to the innovation output. And it not only directly affects the innovation output, but also has an indirect impact through R&D. As to the reverse causality between directors' characteristics and R&D investment, this paper uses the instrumental variables of industry-provincial mean, verifying the robustness of the model. Based on the research conclusions and realistic background, the paper puts forward the following suggestions: The government improves relevant policies, guides the flow of talents with relevant technical experience and good educational background to enterprises. Enterprises should take advantage of the talent and interlock resources to drive innovation investment decisions and facilitate exchange of information and resources, so that the transformation of innovation input to output is promoted.