T The financial services authority (ojk) has an integrated supervisory function in the financial services sector. this function is reinforced in article 5 of the financial sector development and strengthening law (p2sk law). in this case, there was an illegal investment that caused losses to many victims. ojk was unable to carry out optimal supervision due to the large number of similar cases in indonesia. the research problem in this study is: how is the authority of the financial services authority (ojk) regulated in preventing and handling illegal investments under the prevailing laws and regulations in indonesia, and whether ojk’s current role is adequate in preventing and addressing illegal investment practices based on the case study of pt compact sejahtera group. the method used in this study is a normative juridical method, in which this legal research relies on secondary data, consisting of primary legal materials (laws and regulations) and secondary materials (literature). the data was processed qualitatively, and conclusions were drawn deductively. the findings of this research conclude that there are a number of regulations in indonesia that can prevent the occurrence of similar illegal investments. in addition, a reform of ojk’s supervisory model is needed, shifting from an integrated model to a twin peaks model.