In this study, the development of vertebral column and appendicular skeleton were observed in samples of larval and juvenile fat greenling Hexagrammos otakii from hatching through 60 days post hatching (dph), sampled daily in 0-31 day old larvae, and sampled in 5 day interval in 35-60 day old juveniles, by the clearing and staining technique of cartilage and bone. The observation revealed that the vertebral column, heamal arches, neural arches and the pectoral fin appeared to develop from embryonic stage. The heamal spines and the neural spines were formed at 19 dph, the ossification of vertebral column began at 28 dph from anterior to posterior, and completely ossified at 50 dph. The appendicular skeleton developed in the following sequences: pectoral fins, caudal fin, dorsal fins, anal fin and then pelvic fins. Cartilage of pterygiophore of pectoral fins was formed at 20 dph, and the pectoral fin rays were appeared at the same time, at 27 dph when the cleithrum of pectoral fin was ossified. The development of the caudal fin began with the appearance of the hypural at 6 dph, the caudal fin was basically formed at 20 dph due to the fusing of the hypurals, and the caudal fin rays were divided into two parts. The urostyle was the first parts of the caudal fin complex, ossifying at 35 dph. Dorsal and anal fins appeared at 14 dph and 15 dph, respectively. The second dorsal fin was formed earlier than the first dorsal fin, and the formation of the anal fin followed by a caudad and rostrad direction. The ossification pattern was similar to the dorsal fin and anal fin at 40 dph, from anterior to posterior. The pelvic fins began to formed at 16 dph. and ossifying occurred at 31 dph. The vertebral column and the appendicular skeleton were basically ossified at 60 dph. The findings indicated that the development of the vertebral column and fins was an important character in the early life history of fat greenling, as it is closely correlated with the changes from cruising swimming to maneuver swimming and the changes in feeding ability. The fused hypural reflects the higher classification status of fat greenling, which will provide the avoidance of the classification and determination of the fishes, and it is availing for the exploration of the functional trends at the different developmental stages.