研发投资是企业发展竞争优势的关键因素。本文基于资源观，运用233家上市公司2007年-2011年为样本的面板数据，研究可吸收冗余、政治关系强度对企业研发投资强度的直接影响及交互效应。通过F检验表明该回归模型为个体固定效应在此基础上，运用固定效应回归模型，实证研究得出已吸收冗余与企业研发投资强度呈倒U型关系，政治关系强度对企业研发投资强度有正向促进作用，且企业政治关系强度进一步增强已吸收冗余与研发投资强度的倒U型关系。本研究拓展了研发投资的理论研究，同时对于中国企业技术创新投资有实践指导价值。

Research and development (R&D) is the key factor to the firm’s competitive advantages. Based on resource based theory, the paper studies the direct effect and moderate effect of between the absorbed slack, political ties strength and the R&D investment with the panel data of 233 listed companies from 2007 to 2011.After Cross-section Fixed Effects Tests, the paper finds that the absorbed slack has inverted U-shaped relationship with R&D investment and political ties strength has positive effect on R&D investment. Further, it finds that both the positive and negative effects of absorbed slack on R&D investment are more pronounced for list companies with stronger political ties. The paper extends the theoretical research of R&D investment, also it plays the practical value to Chinese firms’ tech-innovation.