Self-bias reflects a fundamental cognitive ability that human beings can distinguish the self from others. There are many instances in which People seem to be biased towards information related to themselves compared with other people in perception, memory and attention. One major account of self -bias effect is that self-related information is intrinsically reward, some recent neuroscience studies demonstrated that self -related stimuli induce neural activity changes in regions recruited during reward. The apparent overlap between self and reward may tell us that the self-related stimuli equaled to those things that have high degrees of value for us, both of them could facilitate the cognitive processing. Therefore, in the present study, we aim to investigate whether the self is similar to high-reward or not. Twenty-three and thirty college students were selected randomly to participant in Exp.1 and Exp.2. The two experiments were divided into two successive sessions separately. Firstly, the participants were asked to associate the geometric figures ellipse or triangle with themselves or the others such as "Ellipse represents yourself and triangle represents a stranger(Exp.1) or your best friend(Exp.2)", then they completed a perceptual matching task in which to decide whether the figure and the label are matched or not. Secondly, they were asked to conduct an Implicit Association Test (IAT) in which to press two response keys to classify the stimuli including four categories (the compatible task refers to the same response key to self-figure and high reward and the incompatible task refers to the same response key to the other-figure and low reward). The results showed that there was a robust self-bias in perceptual matching task-- higher accuracy and faster responses to the figures associated with self than to the figures associated with the other (stranger in Exp.1, friends in Exp.2). In the IAT task, the results showed that neither the RTs between the compatible task and the incompatible task nor the D value was significant when the others was a stranger in Exp.1, which means that there was no similarity between the self and the high-reward. However, both the RT between the compatible task and the incompatible task and the D value were significant when the other was one's best friend in Exp.2, which means that self was similar to the high-reward. To summarize, the similarity of self and high-reward was affected by the other to self, the similarity increased when the other was the friend compared to the stranger. This is due to the context of the reward, when the same response key was assigned to the friend and the high reward, it seemed that the friend was assigned to more money, which made the participants feel being to threaten, but it didn't make too much sense to me when the same response key was assigned to the stranger and the high reward. In conclusion, the similarity of self and high-reward was important for individual survival , and supported the Self-evaluation Maintenance Model proposed by Tesser et al(1988).