It is impossible to talk about underwater cultural heritage and not reflect upon the problem of the commercial exploitation of submerged archaeological sites. The romantic notion of the search for lost treasure embodied in books and popular movies such as the Indiana Jones series takes on a different aspect when we consider that treasure hunting has become one of the most dangerous and devastating threats to the preservation of underwater cultural heritage. Fishing communities, irresponsible sport divers collecting souvenirs or modern-day salvors often equipped with high technology are destroying this newly accessible and rich heritage. Their sole motivation is commercial profit without any concern for archaeological research, preservation of cultural and historical values or the potential for sustainable development involving cultural tourism for the benefit of coastal populations. This article will try to present an overview of the scope of site destruction by commercial exploitation, the loss of scientific information and the strategies used to convince governments and deceive public opinion.