This article aims to explore the concept of justice according to Plato and how its application can be relevant in the context of business law. In his philosophical works, especially in the Republic, Plato describes justice as a condition in which each individual carries out his role in a way that is appropriate to his abilities and characteristics. According to Plato, justice is achieved when each part of society performs its proper function without interfering with each other, which can also be adapted to the business world which has complex social and economic dynamics. In the context of business law, justice can be understood as an effort to ensure that all business actors, whether large companies or small businesses, are treated fairly and given balanced rights and obligations. The application of Plato's principles of justice in business law can involve rules that encourage ethical behavior, fair distribution of resources, and protection of the interests of weaker parties, such as consumers and workers. Business law must ensure that economic activity does not only benefit a few parties, but also creates balance and justice for all parties involved. For example, regulations regarding business competition (anti-monopoly) aim to prevent the domination of one party which can harm other parties, thereby creating harmony in the market. Through a legal philosophy approach, this study will analyze the relevance of Plato's ideas of justice in creating legal regulations that are not only profitable for big business actors, but also provide social and economic justice to society as a whole. Thus, Plato's concept of justice can be a strong basis for designing fair and sustainable business laws. examines Plato's concept of justice and its relevance in business law from the perspective of legal philosophy. Through this approach, we will explore how Plato's principles of justice, such as justice as harmony, distributive justice, and justice as virtue, can be applied in the context of modern business