To understand its osteological development during early stage, 33 larval specimens of Thunnus albacares （9 preflexion larvae, 12 flexion larvae, 12 postflexion larvae, body length： 3.1-8.0 mm） were collected by horizontal trawling at the surface layer by a larval net （1.3 m in diameter, 0.5 mm in mesh size） in the Philippine Sea from August 15th to September 9th, 2022. The specimens were stained and cleared for both cartilage and bone to evaluate their vertebral column and appendicular skeleton development in T. albacares. The results show that the fins were developed in following sequence： pectoral fin, caudle fin, the first dorsal fin and pelvic fin, the second dorsal and anal fin, and finally, finlets. Centrum was formed in a posterior direction. Neural arches were formed in a posterior direction at anterior part of the body and in both anterior and posterior at the middle part of the body. Haemal arches proceeded both anteriorly and posteriorly. Hypural 1 and 2 were fused, and then jointed with the parhypural by cartilage. Hypural 3 and 4 were fused at both ends. Hypural 5 was dissociated. There are 18 precaudal vertebrates, 21 caudal vertebrates, 1 parhypural, 5 hypurals and 2 erpurals in 8.0 mm specimen. The fusions of parhypural and hypurals could enhance the swimming ability for T. albacares. This study can be used as a basis for the fish identification and provides an evidence for the formation of the drift mechanism of T. ablacares larvae.