Law on Electronic Information and Transactions does not provide a criminal threat of an act of online prostitution managed by the prostitute to his customers, but only on acts that distribute, transmit or make accessible electronic information that violates decency. The purpose of this study is to find out the legal arrangements on online prostitution according to ITE Law and to find out the prevention of online prostitution crimes carried out through online media. The type of research used is empirical normative law. The research approach used in this research is the approach to legal systematics. The data analysis used is descriptive qualitative. The results showed that the ITE Law can be used by the police/ prosecutors to ensnare pimps but can not be used to punish commercial sex workers, the threat given is punishable by a maximum imprisonment of 6 (six) years and/or a maximum fine of Rp. 1,000,000,000.00 (one billion rupiah). Prevention efforts that can be done against online prostitution crimes include prevention through education, equality of informal work, prevention through the economic field, and adding social and cultural insights that must be done by the government and requires support and role from many parties including families and communities.