Ordinary people are difficult to keep rational when they do investments, the reason for this is behavior finance. People’s reactions and perceptions are easily affected by their cognition and emotion. This study will focus on the representativeness bias which is people’s shortcut and will give a new angle to think about how behavior influences our investment. In the last, the conclusion of this study is that most people may still not have enough ability to avoid the representativeness bias totally, although they have known the reason and phenomenon of representativeness bias.