Summary. The paper was described antibiogram and heavy metal tolerance of Aeromonas spp. isolated from Asian seabass (Lates calcarifer) hatchery in Malaysia. Aeromonas spp. was recognized as causative agent of motile aeromonad septicemia (MAS) which attack in Asian seabass and caused tremendous loss to fish farmer. Therefore this study was carried out to help fish farmer in selecting the suitable antibiotic in controlling MAS due to Aeromonas spp. diseased Asian seabass fingerling and water sample from the fingerling tank were collected from a commercial farm. Aeromonas spp. was isolated using Glutamate Starch Pseudomonas (GSP). The isolated bacterial isolates were identified using conventional biochemical tests and confirmed with commercial identification kit. 150 bacterial isolates of Aeromonas spp. were randomly selected from antibiotic susceptibility and heavy metal tolerance test. All the bacterial isolates were found to be sensitive to nitrofuratoin, furazolidone, tetracycline, doxycycline, flumequine, oxolinic acid and florfenicol. Therefore, fish farmer may apply those antibiotics as prophylactive or treatment to against MAS due to Aeromonas spp. in Asian seabass culture.

Key words: antibiotic, heavy metal, Aeromonas spp., Asian seabass, Lates calcarifer