[Objectives]  Oxya chinensis undergoes gradual morphological change during development and investigating these changes are important to understanding the form and function of adult grasshopper morphology. [Methods]  The body structure of O. chinensis of different ages was analyzed using geometric morphometric methods and the regularity of the structure of each organ, and its functionality, were inferred. [Results]  There were significant differences in the size of the hindwings, pronotum, sternum, frons and femur of O. chinensis of different ages. The size of these organs increased almost linearly with age. PCA and thin-plate spline analyses show that hindwing shape changed gradually from the fourth instar to the sixth; its cubital region becoming smaller, and the jugal and anal region expanding. The shape of the pronotum, frons and femur also changed gradually with age on the PC1 axis. Thin-plate spline results show that the pronotum became wider, the cheek of the frons broader and the femur slenderer. The adult and larval sternum do not differ significantly in shape, however the adult sternum is larger and has a more prominent femoral attachment area. [Conclusion]  Various functional organs of O. chinensis, such as the hindwings, pronotum, sternum, frons and femur, differ significantly in shape in different developmental stages. The shape of these functional organs changed gradually with age, but, reflecting the functional requirements of each organ, different parts of each organs did not increase equally in size.