Many scholars believe that the stock price surge follows rules of the economy itself. No matter whether it is a bull or a bear market, assets shall ultimately return to their appropriate values. However, historical data show that Chinese investors (either individual or institutional) seldom transact based on the inherent assets evaluation. Instead, they rely more on outside information or mass media reports for investment decisions. For instance, at the early stage of a bull market, stock prices are relatively low and investors are quite conservative in trading, and hence, the number of new accounts is small; while at the later stage, stock prices are overvalued and investors become activated, and hence the number of new accounts is obviously increased. The bull market soar and the bear market plunge are hence not just driven by capital market fluctuation. There are investor-sentiment factors which also influence investors’ decisions and lead to price fluctuations in stock market (Baker et al. 2012; Stambaugh et al. 2012; Stambaugh et al. 2014). As examples, Baker and Wurgler (2007) point out that investor sentiment has a clear effect on the company and the stock. Baker and Wurgler (2006) examine how investor sentiment affects the cross-section of stock returns and predict that investor sentiment more significantly affects securities with valuations highly subjective and difficult to arbitrage. In the Internet era, specifically, the mass media plays the role of sources for most financial information. It disseminates specialized knowledge, solves the problem of information asymmetry between stock investors and listed companies, and strengthens regulation and development of the stock market. However, a considerable fraction of the current media reports deviates from the truth and is full of subjective color. Hence, as a market information system, the mass media sometimes fails to play a normal function, and the investor sentiment as well as investment decisions are unavoidably misled (Meng and Bo, 2010; Li et al. 2014; Sul et al. 2016; Zhang et al. 2016). In the prior literature, Shiller (2015) finds that the popular media optimism is more likely to attract investors to enter the market, and promote the stock market bubble. By examining the relationship between mass media reports and stock returns, Fang and Peress (2009) find that the breadth of information dissemination and stock returns are correlated. Taking the Standard & Poor’s 500 index as a sample, Engelberg and Parsons (2009) show that mass media reports have a strong driving force for investors. According to Tetlock (2007), the higher the degree of pessimism over the mass media, the more active the trading behavior in the market. As listed above, most scholars empirically analyze the impacts of mass media on the stock market from the macro perspective or using macro-level data. However, this paper argues that it is difficult to generalize the conclusions to all individual stock investors only from the macro-based views. We instead focus on the impacts of media effect on investor sentiment and trading behavior from a micro perspective of view. It is conducted by building a binary Logit model and making empirical analysis using data from a micro-level survey with a considerable sample size.