Octopus insularis (Leite and Haimovici, 2008) occurs in a wide region of the tropical Atlantic, inhabiting shallow waters along the coast and oceanic islands of northeastern Brazil, where it is considered the primary target of octopus fisheries. This species was only recently described, and detailed information about its spawning, eggs, and paralarvae is unknown. The objective of this study was to estimate the fecundity, describe the eggs and paralarvae and the duration of embryonic development of O. insularis under culture conditions. Broodstock were captured and transported to the laboratory, where they were acclimated in a closed recirculation water system at 26 °C and 32 salinity. Eggs were obtained from two spawning females and were monitored throughout development; samples of 30 eggs were obtained 1 day after spawning and 1 day prior to the first hatching day, and their length, diameter and weights measured. The duration of embryonic development lasted from 30–38 days and fecundity was estimated as 85,000 eggs per female. The length and width of the eggs on the first day after spawning were 2.13 ± 0.06 mm and 0.82 ± 0.04 mm, respectively, and were 2.29 ± 0.06 mm and 0.92 ± 0.03 mm, respectively, one day before hatching. The newly hatched paralarvae exhibit 3 suckers per arm and a mean mantle length of 1.68 ± 0.13 mm. The chromatophore pattern of paralarvae is conspicuous, with ~ 90–111 chromatophores. A total of 32–40 and 56–69 chromatophores were found on the dorsal and ventral view, respectively. These results are of essential importance for identifying the eggs and paralarvae of O. insularis and in broadening our knowledge of this species.