所得税优惠政策是政府激励企业创新的重要手段，创新效率是影响企业长期绩效的关键因素，现行政策如何影响企业创新效率的分析评价是政策检验的重要环节。本文在对陕西省195家企业深入调研的基础上，运用随机前沿分析方法研究发现： 研发费用加计扣除政策能够提升高新技术企业创新效率，而对非高新技术类企业创新效率没有显著影响；在配对样本基础上，应用双重差分模型分析发现：现行高新技术企业所得税优惠政策并不能显著提高高新技术企业的创新效率。研究提出了强化针对性、实效性的政策建议。

Preferential income tax policy is an important means of stimulating firms’ innovation, and innovation efficiency is a key factor determining firms’ long-term performance. The analysis and evaluation of the effect of current policies on firms’ innovation efficiency is an important procedure for testing policies. Based on a deep investigation into 195 firms in Shaanxi Province, this paper uses the SFA model and finds that pretax additional deduction policy can increase the innovation efficiency of high-tech firms, but has no effect on non-high-tech firms. Based on matching samples, this paper uses difference-in-difference model and analyzes the effect preferential income tax policy applied to high-tech enterprises, and finds that this policy cannot improve high-tech firms’ innovation efficiency significantly. Finally, this paper proposes suggestions for improving the real effect of current policies.