The blue shark (Prionace glauca) is a pelagic, highly migratory shark that is listed by the IUCN as “critically endangered” in the Mediterranean sea since 2016. It is commonly considered as a by-catch species of small-scale, pelagic longline fisheries. Policy-makers have not adopted any measure so far to control its exploitation. This study analyses the trends in the fishery over the last years in the Spanish Mediterranean waters. The results show that blue sharks are now facing a great fishing pressure, particularly from the long line industrial fleet of the Andalusian region, which effectively targets this species. Results also indicate that blue shark cannot be longer considered as a by-catch species because it has become a target species by fishermen. We suggest the need to implement urgent measures to regulate this fishery and conduct new studies to determine whether or not this species should be fished any longer in this area.