The assembly of two-dimensional (2D) nanosheets into three-dimensional (3D) well-organized superstructures is one of the key topics in materials chemistry and physics, due to their potential applications in various fields. Herein, starting from the crystalline metal-organic framework (MOF) particles, a spherical superstructure consisting of metal-organic framework nanosheets (SS-MOFNSs) is synthesized via a simple solvothermal transformation process. After pyrolysis and nitrogenization in ammonia, the SS-MOFNSs are further transformed into the spherical superstructure consisting of boron nitride nanosheets (SS-BNNSs), which preserve the original spherical superstructure morphology. Taking advantage of this unique superstructure, the resulting SS-BNNSs exhibit excellent catalytic activity for selective oxidative dehydrogenation of propane to produce propylene and ethylene. The results of this work provide a novel synthetic strategy to fabricate 3D spherical superstructures consisting of 2D nanosheets for high-performance applications in catalysis, energy storage, as well as other related fields.