A design method of solid waste-based self-foaming expanded ceramsites was studied, and the gas produced by the decomposition of hematite in red mud at high temperature was used to realize self-foaming. In this study, the ceramsites were produced by sintering the raw materials (95% of which were solid wastes) at 1 200 ℃ for 60 min, and the obtained ceramsites have the characteristics of light weight and high strength. The ceramsites particle strength is 4.86~6.75 MPa, water absorption is 0.72%~1.11%, and bulk density is 0.53~0.71 g/cm3. The influence of red mud content on the physical properties, microstructure, phase components and chemical structure of ceramsites was investigated by SEM, XRD, FTIR, TG-DSC and XPS. The results show that with the content of red mud increases from 10% to 25% (mass fraction), the expansion index and water absorption decrease, the bulk density increases, and the particle strength first increases and then decreases. The main reason of the solid waste-based expanded ceramsites with self-foaming behavior is that hematite decomposed at high temperature to released gas, and the gas is entrapped by the liquid phases.