The present study provides the basic information in the fisheries biology and stock assessment for the cobia, Rachynentron canadum in the Southern part of the Arabian Gulf off the United Arab Emirates. A total of 371 individuals were sampled. The length-weight relationships of R. canadum were estimated as W=0.0022*L^3.2536, R²=0.99 for all individuals, W=0.0028*L^3.1875, R²=0.98 for males and W=0.0022*L ^3.258, R²=0.99 for females. According to b values, the growth type of this species was positive allometric growth (b>3), (t-test: p<0.05). Condition factors ranged from 0.60 to 0.77 for males and from 0.61 to 0.85 for females, while the relative condition factor for males ranged between 0.92 and 1.07 and between 0.96 and 1.14 for females. The monthly calculated mean values of the gonado-somatic index (GSI) of females increased from April, reaching the highest value in May then declined in July. The male/female ratio of this species was 1/1.82. The length at first sexual maturity for R. canadum was estimated at 63.31cm and 75.08cm TL for males and females respectively.