Ice structures are widely constructed in cold regions as landscapes or shelters. However, owing to the poor mechanical properties of the material and the masonry construction method, the appearance modelling and building scale of ice structures are limited. It is necessary to discover an innovative high-performance ice material and to establish a large-span ice shell construction method. Based on previous studies, a free-form ice composite shell is designed and constructed with an inflatable formwork. A combined optimization algorithm is proposed to determine a reasonable inflatable formwork for the construction, and exhaustive structural investigations on the behaviour of the ice composite shell under multiple load conditions are conducted. Subsequently, some key technologies for the construction process and health monitoring of the ice composite shell are discussed. The results show that the ice composite material is suitable for the construction of large-span ice shells. The morphological design objectives of the free-form ice shell are achieved based on the previously mentioned optimization algorithm, and the structural analysis provides a theoretical foundation for the structural safety and construction quality of the ice shell. Moreover, the effects of the ambient temperature and solar radiation are not negligible, and further research is required.