In this paper, it’s been tried to examine the legalframework of self-regulatory organizations in Iran and the US’scapital markets and to clarify this matter in Iran and the US (as theinnovator of self-regulation method in some way for setting rules andregulations), with emphasis on laws and practices. To achieve thispurpose, we analyzed this matter from the most important angles;Therefore, in this paper we examined legal origin of self-regulatoryorganizations, their nature, the way they are formed, suspended anddisbanded, the authority for regulating and making rules, adjudicationand authorities investigating members’ (regulatory and criminal)offences. Besides discussing the issues above in detail, we come to theconclusion that the US legal system in this context is similar to Iran,except for a few minor differences.