Rockfish, Sebastes inermis is a ovoviviparous fish distributed around the coastal waters of Korea and Japan. Naturally beared larvae obtained from female fish kept in the aquarium were reared for three months in the laboratory. The naturally healed larvae were 6.05mm in average total length(TL) with $8+18{sim}19=26{sim}27$ myomeres. Melanophores were distributed on the top of head, around the intestine tube and on the dorsal and ventral margins of the tail, but none on the pectoral fins. The larva(7.1mm in TL) consumed all the yolk and oil globule, in 7 days after bearing, and jaw bones were more rapidly ossified than vertebrae and cranium. In 21 days after bearing, the larvae averaged 8.50mm in TL and the caudal notochord flex $45^{circ}$. Fin development in S. inermis larvae proceeds in the following sequence: caudal, pectoral, dorsal, anal and ventral fin. Individuals $17.6{sim}20.8mm$ in TL($65{sim}69$ days after bearing) are regarded as the juvenile stage. All fins bones was nearly completed in this stage.