The karyotype of fish plays an important role in the preservation of germplasm resources, identification of genetic relationships, exploration of evolutionary processes, construction of genetic maps, and fish classification and breeding. Pseudocaranx dentex is a new target for aquatic resource development, with high economic and breeding value. However, little is known about its genetic background. In this study, chromosome samples from gill and fin tissues of P. dentex were prepared by the hot air-drying method. Karyotype was subsequently analyzed by Giemsa staining. The karyotypes of 106 metaphase cells in four P. dentex juveniles were analyzed. The results showed that the mitotic phase with 48 diploid chromosomes accounted for 86.79% of the observed mitotic phases, all of which were telocentric chromosomes; the karyotype formula was 2n=48t; the number of chromosome arms was NF=48; the relative size of the chromosomes in this species varied from 5.921% (±0.276%) to 2.052% (±0.210%). No heteromorphic sex chromosomes were observed. Neither satellite nor secondary constrictions were observed either. This is the first study on the characteristics of karyotype of fish from the genus Pseudocaranx, compared with 34 species from 15 other genera of the family Carangidae. The karyotype of P. dentex is consistent with the karyotype characteristics of typical high-level groups, according to the evolution of teleost chromosomes. This study provides basic data on cytogenetic characteristics and evolution processes for the effective protection and rational development of this high-quality resource, P. dentex.