Trachurus japonicus (scientific name: Trachurus japonicus) is a fish belonging to the family Scangidae and genus Trachurus. The body is subcylindrical and slightly flattened on the side. Kiss tip. Lipid eyelids are well-developed, with the front reaching the front line of the eye and the rear reaching near the posterior edge of the pupil, leaving a semicircular gap. The upper and lower jaw each have a row of fine teeth, and the hoe bone, palate bone, and tongue surface all have teeth. The chest is completely scaly. The lateral line is almost straight from the starting point to the bottom of the starting point of the second dorsal fin, and then diagonally descends to the bottom of the 7th to 9th fins of the second dorsal fin, starting from the tail handle and forming a straight line; The lateral line is covered with ridge scales, which are tall and strong, and are important features of this genus. There is also a pair of lateral lines on the back, extending along the base of the dorsal fin to below the starting point of the second dorsal fin base. No detached fins. The back of the body is blue-green or chartreuse, and the belly is silvery white. There is a black spot above the posterior edge of the operculum. The dorsal fins are dark, the pectoral fins are light, and the other fins are yellow.