This study addresses a core question: what is the magnitude of the perceived injustice associated with given departures from perfect just in Taiwan? We can discuss ideas of justice from various perspectives and in many ways. The focus of this study is on personal earnings and this research examines whether Taiwanese people perceive their income as just. In the perspective of social scientists, first of all, a subjective construct and closely related to the perception of the observer. Secondly, the sense of justice is a process of comparison between observers’ just rewards and actual rewards. Finally, each member of society forms judgements concerning the justice or injustice of the amount received by him/herself as well as everyone else. When a justice evaluation is concerned with one’s own rewards, it is called a reflexive justice evaluation. In contrast, when a justice evaluation is concerned with another’s rewards, it is called a nonreflexive justice evaluation. The data used in this study were drawn from the International Social Survey Programme: Social Inequality IV project. The findings indicate that the magnitude of perceived injustice among Taiwanese people is highly related to age, social class, and level of education, which are the determinants of the structure of personal earnings and of opportunities for human development.