中国的金融衍生品市场发展历史较短，其交易量、市场成熟度、产品丰富度等相比于国外发达金融市场仍有较大的提升空间。沪深300指数期权于2019年12月23日正式上市，这是中国内地第一支以实际股票指数为标的资产进行交易的期权，代表着中国衍生品市场迎来全新的发展阶段。由于中国的期权市场发展时间较短，有关期权市场对现货市场影响的研究依然不够充分，但却具有很大的理论和现实指导意义。本文将研究视角聚焦于股指期权市场对于现货市场效率的影响，将指数和成份股市场数据和经营数据作为样本，分别利用GARCH模型和双重差分模型从多个角度研究了沪深300期权的上市是否提升了标的现货市场的运行效率，并通过倾向匹配得分、安慰剂检验、Heckman两步法等多种稳健性检验方法提升了研究的可信度。此外本文还从流动性和信息披露质量两个角度检验了期权对现货市场效率的影响机制。本文研究发现：1）从波动性的角度来看，股指期权的推出总体上使得标的市场的信息吸收速度加快，市场滞后期信息对当期波动的影响更小，且波动的不对称性弱化；2）从指数价格运动的长期记忆性角度来看，股指期权的上市削弱了标的市场前后期价格增量之间的相关性，以Hurst指数衡量的市场效率指标提升，说明市场价格的运动形态更加接近于随机游走；3）从个股定价效率的角度来看，期权有效减少了滞后期市场信息对于个股当期的影响，促进了个股价格吸收市场信息的速率，个股的资产定价效率得到提升；4）沪深300期权通过提升市场流动性以及改善市场信息不对称性的方式增强了现货市场的效率。本文的研究结论支持股指期权的上市显著改善了现货市场的效率，提升了整体市场有效性。因此有序引导投资者合理使用股指期权等衍生品，扩大股指期权标的资产的覆盖范围从而提升市场的资源配置能力和资产定价能力是推动我国资本市场健康、蓬勃发展的有效措施。

China's financial derivatives market has a relatively short history of development, and its transaction volume, market maturity, and product richness still have a lot of room for improvement compared to developed foreign financial markets. The CSI 300 index option was officially listed on December 23, 2019. This is the first option in mainland China to trade the underlying asset with the actual stock index, representing a new stage of development for the Chinese derivatives market.Due to the short development time of China's options market, the research on the impact of the options market on the spot market is still insufficient, but it has great theoretical and practical guiding significance. This paper focuses on the impact of the stock index options market on the efficiency of the spot market. Taking the index and constituent stock market data and operating data as samples, the GARCH model and the difference-in-difference model are used to study whether the listing of CSI 300 options has improved the operating efficiency of the underlying spot market. Also this paper uses multiple robustness testing methods such as propensity matching scores, placebo tests, and Heckman two-step methods to improve the credibility of the research. In addition, this paper also examines the impact mechanism of options on spot market efficiency from the perspectives of liquidity and information disclosure quality.This paper finds that: 1) From the perspective of volatility, the introduction of stock index options generally accelerates the information absorption rate of the underlying market, the market lag period information has less impact on current volatility, and the volatility asymmetry is weakened; 2 ) From the perspective of the long-term memory of the index price movement, the listing of stock index options weakens the correlation between the price increments of the underlying market, and the market efficiency index measured by the Hurst index improves, indicating that the movement pattern of the market price is closer ;3) From the perspective of individual stock pricing efficiency, options effectively reduce the impact of market information in the lag period on the current period of individual stocks, promote the rate at which individual stock prices absorb market information, and improve the asset pricing efficiency of individual stocks; 4) CSI 300 options enhance the efficiency of the spot market by enhancing market liquidity and improving market information asymmetry.The research conclusions of this paper support that the listing of stock index options significantly improves the efficiency of the spot market and enhances the overall market effectiveness. Therefore, it is an effective measure to promote the healthy and vigorous development of my country's capital market by orderly guiding investors to rationally use derivatives such as stock index options, and expanding the coverage of the underlying assets of stock index options to enhance the market's resource allocation and asset pricing capabilities.