Otoliths are located in the inner ear of bony fishes, which representspecies-specific morphology. Thus, these structures could be used as an importanttrait in fish identification. However, little such information is available on gobies,one of the most diverse bony fish groups, which are commonly difficult to identifyusing external morphology. The present study provides information on the otolithmorphometry of nine species of gobies (in three families, i.e., Eleotridae, Gobiidae,and Oxudercidae) caught in the Ba Lat estuary of the Red River in 2019. Otolithmorphology of species in one family resembles, but it is clearly different betweenspecies in the same genus. Otolith length and weight changed proportionally to thefish’s growth, but their shapes were not much changeable in one species. Theseresults are valuable for further investigations into a taxonomy of gobies usingotoliths and confirm the species-specific characteristics of this structure in fishidentificationOtoliths are located in the inner ear of bony fishes, which representspecies-specific morphology. Thus, these structures could be used as an importanttrait in fish identification. However, little such information is available on gobies,one of the most diverse bony fish groups, which are commonly difficult to identifyusing external morphology. The present study provides information on the otolithmorphometry of nine species of gobies (in three families, i.e., Eleotridae, Gobiidae,and Oxudercidae) caught in the Ba Lat estuary of the Red River in 2019. Otolithmorphology of species in one family resembles, but it is clearly different betweenspecies in the same genus. Otolith length and weight changed proportionally to thefish’s growth, but their shapes were not much changeable in one species. Theseresults are valuable for further investigations into a taxonomy of gobies usingotoliths and confirm the species-specific characteristics of this structure in fishidentification