Ceramic and inorganic materials have extraordinary physical properties, such as high modulus, high strength, high hardness and heat resistant. However, the low toughness hinders the wide application of ceramic. Although ceramic can withstand high load in the elastic stage, once the crack emerged inside the bulk ceramic, it will propagate fast and cause the dramatic failure of the whole structure. To solve this problem, several toughening mechanisms has been developed, such as bridging mechanism and crack deflection. The main idea is to hinder the crack propagation or increase the energy needed for the crack propagation. One effective way is the add reinforcements in the ceramic to create reinforced ceramic composites. Graphene has been verified to be a promising candidate for reinforcing ceramic matrix composites due to its extremely high elastic modulus (~1 TPa) and intrinsic strength (~130 GPa). However, similar to ceramics, graphene also has brittle fracture behavior, and its fracture toughness is only about 4 MPa·m1/2. h-BN is a kind of 2D material which has a similar lattice structure to graphene, with B and N atoms adjacent to each other. It is well known for it dielectric properties and widely used as dielectric substrate and protective layer. People has found its robustness since it can dramatically increase the sample survival rate if used as protective layer. However, its toughness mechanical property has not been systematically studied since recent years. In this thesis, the mechanical properties of h-BN, interfacial mechanical properties of h-BN/ceramic nanocomposites and additive manufacturing h-BN/silica nanocomposites are shown. The intrinsic toughening mechanism, h-BN/ceramic nanocomposites toughening mechanism are systematically discussed. In chapter 2, the intrinsic toughening fracture behavior of single layer h-BN was firstly introduced and a dual fracture mode (asynchronous and synchronous fracture) of multilayer h-BN caused by interlayer mechanical coupling effect was shown. In chapter 3, by using nanoindentation-assisted micro-mechanical devices integrated with scanning electron microscopy (SEM), the interfacial sliding and failure behaviors between h-BN and PDC were systematically studied. In chapter 4 and 5, 2PP 3D printing technique was developed to create high quality silica and h-BN/silica nanostructures with sub-200 nm. High Q microtoroid resonators and strong photoluminescence of rare earth doped silica nanostructures were demonstrated and mechanical properties of h-BN/silica nanocomposites was studied. Overall, this thesis contributes to the knowledge of toughening mechanism of h-BN and h-BN nanocomposites and shows the advanced way to fabricate inorganic nanocomposites with nanoscale resolution.