Spinoza studies have paid little attention to the concept of justice for centuries. However, he refers to it quite often in different contexts, especially in his mature texts. More specifically, he defines it as synonymous with suum cuique tribuere, even though he fails to provide a reasonable account of how this traditional legal expression fits into his philosophical system. This article shows that there is a relevant philosophical dimension in Spinoza’s treatment of the suum cuique that emerges out of his notion of equality. The main section identifies the connection between Spinoza’s references on justice as suum cuique and the different conceptions of equality that are inherent in his system (an ontological, a metaphysical, a productive (ethical), a legal, and a political equality). The conclusion tries to answer the question of whether such an understanding of the suum cuique as equality constitutes a theory of justice or not.