The reproductive potential of the European pilchard (Sardina pilchardus) during the spawning season in the Adriatic Sea exhibits significant seasonal and biological variations. In a study conducted from October 2023 to April 2024, 1085 specimens of sardine, ranging in length from 11,3 to 17 cm (mean ± SD; 13.37 cm ± 0.923 cm), caught using a purse seine fishing method specifically targeting sardines, were analyzed. A total of 309 males (39.3%) and 478 females (60.7%) were recorded, with a female-to-male ratio (♀/♂) of 0.61. The values of gonadosomatic index (GSI) and gonad weight (Wg) peaked in December and March and progressively declined after the spawning period. Oocyte diameters were measured for all studied months: early primary oocytes from stage I had an average size of 61 μm, stage II (primary oocytes) averaged 168 μm, stage III (secondary oocytes) averaged 202 μm, and tertiary oocytes from stage IV averaged 329 μm. Overview of all histological preparations revealed the presence of post-ovulatory follicles (POFs), and according to their frequency of occurence the spawning frequency was determined at 2.5 days.