Provided is an orientation agent for NMR spectroscopy containing a nanosheet which is easy to prepare, excellent in handleability, economic efficiency and versatility, and is capable of being stably aligned to the magnetic field. The nanosheet is coated with a compound having a molecular weight of 1,500 or more and containing 35 or more functional groups per molecule, said functional groups being composed of at least one selected from a hydroxy group, an amino group, an amide group, a carbonyl group, a carboxyl group, a sulfo group, a phosphate group, an imidazole group and a guanidine group.