This study focuses on whether the mispricing of investor has relevance for firm¡¦s investment decision. In other words, it tries to test the relation between mispricing of investor and managers¡¦ catering behavior. In addition, this study divides Taiwan¡¦s companies into three cases: Listed and following listed companies, OTC companies and companies under the counter. The period of this study from 1986 to 2009, it excludes firms with negative book value of assets, and only uses the positive capital expenditure data. This paper divides the sample into various subsamples discussed separately. For example, it uses the R&D ratio as the proxy for information transparency and explores that information transparency may affect manager¡¦s catering behavior in the different subsamples. Besides, this study also separates the companies from different stock turnover rate to discuss whether the impact of mispricing to the rate of investment will be different. The results showed that indeed mispricing change the rate of investment of companies. After that, this paper controls the independent variables which may affect the company¡¦s profitability to figure out the abnormal rate of investment. Finally, this study finds that abnormal rate of investment result in a poor return of companies. That is to say, when a manager caters the mispricing of investor in stock market, afterwards, may lead to a poor return of companies. In the view of investors, when the market¡¦s sentiment that is too warm, many companies begin to invest in plant. At this time, investors shall examine whether the investment of companies is efficient.