This study aimed to investigate otolith in Rachycentron canadum in the Persian Gulf and Oman Sea. Sampling lasted from March 2014 to April 2015 in Khouzestan to Sistan and Baloochestan waters. During this period 30 specimens of R. canadum were caught and studied. Trawling time was 2-2½ hours and trawling depth was considered as 10-100 m daily. All the fish were identified and their otolith was extracted for verification. Investigation of otolith morphometric characteristics (length, breadth, weight, perimeter and area) were conducted. Otolith in R. canadum was small, with average stretch and low thickness. We conclude that the otolith appearance and morphometry can be used as a key to identify the species.