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Bycatch is defined as “the accidental capture of non-targeted species or individuals of undesirable size ranges of the target species by non-selective fishing gear”. It is widely recognized as one of the main threats to marine biodiversity, potentially affecting vulnerable species and altering ecosystem structure and functioning. Consequently, increasing attention has been given in recent years to improving bycatch monitoring and mitigation strategies. Within the framework of the scientific cooperation agreement between CNR-IRBIM and ISPRA, supporting the implementation of the Marine Strategy Framework Directive (2008/56/EC; Legislative Decree 190/2010). The activities will support Descriptors 1 and 3 and the D03-03 monitoring programme (MWEIT-D03-03) in the Strait of Sicily (GSA 16). Fishery-dependent data were collected to assess the bycatch of vulnerable marine species, including elasmobranchs, sea turtles, marine mammals, and seabirds. The study involved four commercial fishing vessels from the ports of Mazara del Vallo, Sciacca, and Licata, including three bottom trawlers and one longliner. Data was collected through two complementary approaches: self-reporting by fishers and on-board observations by scientific observers. Preliminary results showed that the accidental captures of 482 individuals were composed almost exclusively of Batoidea and Selachii, with just one individual of Caretta caretta (Linnaeus, 1758). The most frequently reported species were Scyliorhinus canicula (Linnaeus, 1758) (36%), Squalus blainvillei (Risso, 1827) (41%), and Raja clavata (Linnaeus, 1758) (13%). These bycatch events were mainly recorded by the trawling fleet of Licata and Mazara del Vallo.   These findings provide an initial overview of the species most affected by accidental catches of vulnerable species and their spatial distribution in the Strait of Sicily. The gathered data help fill knowledge gaps for endangered, threatened, and species currently listed as Data Deficient on the IUCN Red List, thereby supporting ecosystem-based fisheries management and conservation measures in the Strait of Sicily.