Dolphifish (Coryphaena hippurus), purplish amberjack (Seriola dumerili), Commerson's mackerel (Scomberomorus commerson) and longtail tuna (Thunnus tonggolare)all important commercial fish species. The global demand is increasing day by day. In this study, reproductive biology research, fish breeding, and artificial insemination of dolphifish and amberjack will be conducted. Thereafter, the developmental process of embryos and the changes of fry morphology will be observed, and fry of purplish amberjack will be produced, and release to the sea area to recover the marine resources, so as to achieve the goal of sustainable development of fisheries. It is spawning season of Commerson's mackerel extended from March to August, and peak from March to May in the waters of the central Taiwan Strait. Postovulatory oocytes and hydrated oocytes were present in the gonads. Therefore, the Taiwan Strait appeared to be spawning grounds of Commerson's mackerel. This research will collect live fish and establish semen cold storage and semen cryopreservation, carry out egg cell culture and explore the final maturation-inducing steroid in longtail tuna.