Like other lanternsharks, the brown lanternshark is ovoviviparous, meaning the young hatch inside the mother's uterus and are sustained by a yolk sac. The litter size is 9–18. Newborns measure in length. Males reach sexual maturity at a length of , and females at a length of . A study of brown lanternsharks in Suruga Bay by Yano and Tanaka (1989) found a 23% prevalence of hermaphroditism within the population. Of the 16 hermaphrodites examined, 15 were functional females (and some were pregnant) that also possessed well-developed claspers (male intromittent organs), while one was a functional male with ovarian tissue in the left testis. The reason why so many sharks in Suruga Bay are hermaphroditic is unclear, but has been speculated to relate to pollution.
