A facile single-source precursor method has been applied for the selective synthesis of MnS nanocrystals (NCs) with well-defined shapes and crystal structures such as hexapod, octahedral, hexagonal shaped alpha-MnS NCs, and pencil-shaped gamma-MnS NCs. The effects of the composition of precursor, reaction temperature, and the heating rate on the morphologies, and crystal structures of MnS NCs were systematically studied for the first time. (C) 2012 Elsevier Inc. All rights reserved.