The black seabream (Acanthopagrus schlegelii) is an economically important species for both fisheries and aquaculture. Over the past decade, more than 10 million hatchery black seabream fry were routinely released into the coastal water off Taiwan. While the genetic effects of these hatchery A. schlegelii in the wild have received increased much attention, they were still poorly understood and rarely characterized. One of the main reasons is the lack of effectively molecular markers to address this issue. In the present study, we aimed to develop a standardized molecular assay for the large-scale genetic analysis of A. schlegelii. One hundred twenty-eight microsatellite markers were selected and validated using multiplex PCR to determine the ideal markers for genetic analysis of black seabream. We have found two sets of microsatellite markers (ASplex1 and ASplex2) that consistently amplified the amplicons and detected the allelic variations in the multiplex PCR assay. ASplex1 and ASplex2 are composed of 6 and 7 microsatellite markers, respectively. Taken together, we have successfully developed a robust (reliable and cost-effective) marker-assisted molecular approach for the large-scale genetic analysis of black seabream in future studies.