Copyright infringement in Indonesia is rife, one of which is piracy of books that are printed freely without permission from the Author or Publisher. This case widens when sales are made online. Based on a survey by the Indonesian Publishers Association (IKAPI) in April 2020, 25% of PDF formats were distributed free of charge, then 54.2% sold pirated physical books through Marketplace, and 20.8% sold PDF format books. The Director General of Intellectual Property Rights as a government administrator in the field of law in cases of copyright infringement, the legal process can be pursued through complaint offenses. This means that the Issuer must first report it to the Director General of Intellectual Property Rights. If the marketplace does not filter, legal efforts to protect the rights of authors or publishers are not maximized. What legal remedies can be taken by parties who are harmed by piracy of books that are traded through the Marketplace. This study aims to explain and analyze legal protection against piracy of books traded through the Marketplace in the perspective of copyright protection in Indonesia, legal remedies that can be taken by parties who are harmed by piracy of books traded through the Marketplace and obstacles in law enforcement against book piracy. traded through the Marketplace. This research is a normative juridical research, the approach used is a statute approach and a comparative approach. The data source is in the form of secondary data consisting of primary legal materials, secondary legal materials, and tertiary legal materials. Data collection techniques were carried out by systematically classifying and integrating three legal materials, both primary, secondary and tertiary. The data that has been collected is analyzed qualitatively then presented with a descriptive method then conclusions are drawn to answer the problems raised in this legal research. The results of the study show that first, legal protection against piracy of books traded through the Marketplace in Law Number 28 of 2014 concerning Copyright can be repressive and preventive. Repressive legal protection is regulated in Article 114 of the Copyright Law, which means that you can be convicted and pay a criminal fine of one hundred million rupiah. Preventive legal protection is regulated in Article 55 of the Copyright Act, namely by reporting to the relevant institution. It is recommended that the Directorate General of Intellectual Property Rights under the auspices of the Ministry of Law and Human Rights, the Ministry of Communication and Information and Marketplace supervise sellers who offer books without a publisher's permission.