This quantitative empirical research analyses secondary school students' representations of social justice in different regions of Spain. The 'Social Justice Representation Questionnaire - SJRQ' has been designed and implemented to conduct an empirical analysis of Social Justice within the field of education. This instrument is based on the three-dimensional model of social justice (redistribution, recognition and representation). The participants in this study comprised 3229 secondary education students aged from 12 to 21 years old. The participants attended 20 public schools in five Autonomous Communities of Spain. This study aims to determine how the concept of social justice develops in secondary education students of different educational levels and whether gender is a relevant variable. The results confirm that social justice representations of secondary education students follow a developmental trend because students at upper educational levels have a closer vision to social justice. Moreover, females manifest a greater predisposition towards social justice than males. This study confirms that the SJRQ is a useful tool to train Social Justice oriented citizens and to develop training programmes adapted to different understanding levels.