This article addresses the debated question whether the abandonment of drifting fish aggregating devices (dFADs) is illegal from the perspective of international marine pollution law. It first provides a brief overview of the general international legal framework for the protection of the marine environment contained in Part XII of the United Nations Convention on the Law of the Sea (UNCLOS). Next, this article examines the specific international legal regime concerning pollution by dumping, namely the Convention on the Prevention of Marine Pollution by Dumping of Wastes and Other Matter (LC) and its 1996 Protocol (LP). Thereafter, it analyzes the international legal regime concerning pollution from vessels under the International Convention for the Prevention of Pollution from Ships (MARPOL), Annex V of which contains provisions on the discharge of garbage, including fishing gear. The article concludes that while the delimitation of the two regimes is difficult, the abandonment of dFADs contravenes either the LC/LP or, if a different interpretation is adopted, MARPOL Annex V. The decision as to which of the two regimes is applicable depends on whether dFAD abandonment can be classified as “incidental to, or derived from the normal operations of vessels […] and their equipment” or not. In any event, the negligent loss of dFADs violates MARPOL Annex V. The article also shows that there is some State practice and opinio juris that suggests a parallel applicability of the two regimes even with respect to deliberate dFAD abandonment.