The current study investigated two types of punishment (prosocial and proself punishment) in the ultimatum game (UG) and examined the impact of individuals' prosocial orientation on the costly punishment in the UG in a representative sample of Chinese undergraduate students (N = 344). The prosocial orientation was measured with individuals' performance in the dictator game (DG), social value orientation (SVO), and the personal norm of reciprocity. Prosocial and proself punishers were established with responses in advantage and disadvantage offers in the UG. Results showed that prosocial and proself punishers coexisted in the UG, and prosocial punishers were more likely to be prosocial in SVO and allocated more resources to the recipient in the DG than proself punishers, but differences in positive/negative reciprocity between prosocial and proself punishers were not found. Further regression analysis found that SVO type and generosity in the DG could predict the type of punishers in the UG, but not positive/negative reciprocity. These findings indicate that individuals rejecting unfair offers in the UG may be motivated by either prosocial motivation with strict fairness concern (prosocial punishment) or selfish motivation with maximizing self-interest concern (proself punishment). Moreover, SVO type and generosity in the DG might be effective measures to discriminate prosocial and proself punishers in the UG.