Abstract: To investigate the intertribal body size differentiation within Cassidinae, Cassidinae specimens were collected using the transect method in the border regions of Jiangxi, Guangdong and Hunan. Morphological traits including body weight, length, and width were measured, and body size variation and allometric growth patterns among tribes were analyzed by non-parametric tests and allometric growth models. The results indicated that a total of 12 tribes of Cassidinae were recorded in the eastern Nanling Mountains, with Hispini being the most species-rich tribe(31 species). Significant differences were found among tribes in terms of body weight, length, width, and length-to-width ratio. Based on body size, the tribes could be categorized into three groups:small-sized(e.g., Notosacanthini, Hispini), medium-sized(e.g., Gonophorini, Cassidini) and large-sized(e.g., Basiprionotini). The length-to-width ratio further classified body shapes into three types:broad(Cassidinae groups), intermediate and slender(e.g., Gonophorini, Leptispini). Allometric analysis revealed significant allometric relationships in all models except for the body weight-body width relationship in Oncocephalini. Specifically, positive allometry was observed in the body weight-body length model for Leptispini and Callispini.