| Sumario: | Hatchery production of juveniles is considered fundamental for the development of sea cucumber aquaculture. In Brazil, where Holothuria grisea is considered the holothuroid with the greatest potential for aquaculture, few studies in this regard have been carried out. This species occurs along the Brazilian coast, up to Santa Catarina State, its southern limit of distribution. The objective of this work was to evaluate techniques for induction of spawning and cultivation of H. grisea larvae, recording their growth, survival, and development. Adults were collected in a sandy-rocky substrate in the intertidal zone, in Armação do Itapocoroy, Penha, SC, Brazil in February 2021. After determining the gonad index of broodstock, spawning induction and fertilization of the oocytes were performed. The larval cultures were carried out in static system, with daily water changes, and two methods were tested: one with complete water change and the other with partial renewal (80%), where the larvae were kept in the cultivation units. The gonad index of the broodstock was low (0.85%). Two specimens responded to induction stimuli, one female, which released 150,000 oocytes (135.8µm). After 48 hours, there was 23.3% recovery of initial auricularia (375.5µm). After 20 days, final auricularia with an average length of 876.8µm (±65.5) were observed, and final survival was 0.51% (±0.04) in the treatment with total water change. In the other treatment, however, there were no surviving larvae at the end of the experiment. With this first trial to reproduce H. grisea in its southern limit of distribution, it is concluded that it is possible to induce spawning and to cultivate H. grisea larvae using techniques used for other holoturoids, even though a low gonad index of the broodstock was recorded. It is necessary to continue studies for a better understanding of the reproductive cycle of H. grisea and to determine appropriate cultivation protocols for this species.
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