Boron nitride (BN) nanostructures with complementary functions to their carbon counterparts are one of the most intriguing nanomaterials. Here we devote a compact review on the syntheses of BN nanomaterials: typical zero-dimensional (0D) fullerenes and nanoparticles, one-dimensional (1D) nanotubes and nanoribbons, two-dimensional (2D) nanosheets as well as three-dimensional (3D) nanoporous BN. Combining low-dimensional quantum confinement and surface effects with unique physical and chemical properties of BN, e.g. excellent electric insulation, wide band gap, and high chemical and thermal stability, BN nanomaterials have drawn particular attention in a variety of potential applications, e.g. luminescence, functional composites, hydrogen accumulators, and advanced insulators, which are also reviewed.