Maximum sustainable yield, popularly known by its acronym msy, is perhaps the most disputed concept in the realm of international fisheries law. The first part of this article briefly describes the genesis, development and subsequent adoption of the msy concept in international, regional and national fisheries management instruments. The second part documents the criticisms that the msy concept has generated to date and seeks to find out the legal status of the msy concept in international fisheries law. The third part of this article critically examines the adoption of the msy concept in the legal and policy regime for marine fisheries in Bangladesh. The article argues that more rigorous provisions for conservation of marine ecosystem should be incorporated in fisheries management policies of Bangladesh instead of solely relying on the msy concept as an objective of fisheries management.