Rapid human population growth has increased demand for water supply, food security, electricity, and flood mitigation worldwide. To address these challenges, governments have invested heavily in the expansion of water infrastructure. However, there is substantial evidence that globally, this infrastructure impacts aquatic ecosystems and can have a significant impact on the persistence of migratory fish species. Despite being well understood globally, the impacts of dams on migratory fish have been given scant attention in Indonesia. Thus, considerations for fish are rarely included in river development planning frameworks. To document the impact of riverine barriers on Indonesian freshwater fish, we surveyed multiple sites, using three different gears (gillnets, castnets, and bait traps), upstream and downstream of Perjaya Weir in the Komering River. The study revealed 13 of 36 species were found only downstream of the weir and five of 36 species were found only above the weir. The local extirpation of many species from upstream areas suggests that the Perjaya Weir hinders fish migration. Despite containing a fishway, the results indicate that fish are not successfully recolonizing upstream reaches.