Trammel nets are one of the effective fishing gears widely used in small-scale fisheries. Understanding their selectivity is crucial for fisheries management in determining appropriate mesh sizes that optimize the capture of target species while reducing bycatch and discards. This study aimed to evaluate the selectivity of trammel nets with different mesh sizes (1.75 and 2 inches) for capturing the croaker species (Otolithoides pama and Panna microdon) in the Musi River Estuary, South Sumatra, Indonesia. Experimental fishing was conducted to collect total fish length data, resulting in 248 specimens across 16 species. Holt's Model (normal location model) was applied to estimate the trammel net selectivity, while the size distributions were compared using the two-sample Kolmogorov-Smirnov (K-S) test. The results indicated that smaller mesh sizes caught a greater number of fishes, but larger mesh sizes obtained catches with a greater total length. The K-S test revealed significant differences in length-frequency distributions for P. microdon (P=0.023<0.05) and combined croaker species (P=0.019<0.05), but no significant differences for O. pama (P=0.068>0.05).  The optimal catch sizes for both croaker species were above the length at first maturity recorded for O. pama. Accordingly, the trammel nets with 1.75 and 2-inch mesh sizes are still suitable for capturing mature croaker fish in the Musi River Estuary and may help reduce the capture of immature fish. These findings would provide valuable empirical evidence for fisheries management to determine appropriate inner-panel mesh sizes for the sustainable exploitation of both croaker species under study.