Self-prediction refers to a psychological process of predicting future behavior by oneself. A large number of studies have shown that self-prediction has varying degrees of optimistic tendency in most cases. There are three main types of self-prediction optimistic tendency: optimism bias, planning fallacy, and overconfidence. Their influencing factors can be divided into two categories: individual factors and situational factors. The mechanism of optimistic tendency includes nonmotivation mechanism（focalism,egocentrism） and motivation mechanism. Future researches need to pay  attention to the research of cognitive neural mechanism of optimistic tendency using functional magnetic resonance imaging （fMRI） and event-related potentials （ERP）. When conducting research, researchers should focus on the standards of sampling, and choose the appropriate scale and paradigm to guard against the statistical illusion.