The present work was meant to the reproductive cycle of the rabbitfish Siganus canaliculatus, one of the economically important marine fish inhabiting the Arabian Gulf of Saudi Arabia coast. The future expectations of development of Siganus mariculture were described. This study revealed the sex ratio, gonads maturity stages, size at first sexual maturity, spawning season, ova-diameter and fecundity. The length at first sexual maturity (Lm50) was found to be 18 cm and 19 cm for males and females, respectively. Fishes larger than 22 cm total length of both sexes were found to be fully mature. Although, the gonado-somatic index (GSl) of Siganus canal iculatus differed significantly (P > 0.05) between males and females, it exhibited the same trend for both, where GSI reached its maximum values (peaks) of 18.0 and 22.5 during May for males and females, respectively. The spawning season was found to be short and occurred during the period from April to June, with a high peak during May, which means that one spawning season was exhibited. The egg-diameter distribution was significantly variable in the ripe ovaries with largest egg diameters ranging from 0.3 to 0.4 mm, which constitute about 88 % of the total eggs and revealing one peak during May. Absolute fecundity was increased with increasing length, weight and age of the fish. Fecundity exhibited a curvilinear trend or exponential equation with fish length, fish weight and fish age. The mean sex ratio (Males: Females) for the whole year was 1:1.13. It was recommended that capturing of fish smaller than 20 cm total length should be prohibited to protect the spawning stock biomass of rabbitfish S. canaliculatus on the long run. Also, many aspects for mariculture potential were included.