The yellowfin tuna is a pelagic species with significant potential and economic value in the waters of West Sulawesi Province. This resource is primarily harvested through tuna handlines and purse seine units, and these fishing methods continue to increase. As a result, proper management is essential to ensure the optimal productivity and sustainability of the tuna fishery. The research aimed to provide detailed insights into various fisheries aspects, including catch per unit effort (CPUE), utilization rates, and the size distribution of catches from small-scale tuna fisheries, particularly those employing handlines in West Sulawesi waters. In this study, the estimated catch and effort to the maximum sustainable yield (MSY) of the yellowfin tuna were examined based on CPUE data collected over 16 years (2007–2022). Additionally, the size structure of the tuna caught and their growth patterns were analyzed across different seasons (September 2022–August 2023). The MSY analysis was conducted using an equilibrium approach, applying the Schaefer and Fox models. The findings indicated that the average CPUE for the yellowfin tuna in West Sulawesi is 33.6 tons per unit per year, with an estimated CMSY of 18,565.9 tons per year and EMSY of 344 units per year. However, the biomass trend is declining, and overfishing has been observed over the past five years. The size structure of the yellowfin tuna caught across seasons ranges from 17 to 186cm, with most fish being undersized, except during the eastern season. The growth pattern of the yellowfin tuna during the eastern season is isometric, while in the other three seasons, a positive allometric growth was shown. Given the current pressure on the yellowfin tuna stock, government intervention is necessary to implement effective management measures to prevent further overexploitation and to ensure the resource's long-term sustainability.