In this work, a facile and low-cost one-pot method was developed to prepare metastable wurtzite copper indium sulfide (CuInS2) nanocrystals (NCs) under atmospheric conditions. When 1-dodecanethiol and oleylamine were used as the mixed solvent, high quality metastable wurtzite CuInS2 NCs were obtained which can stably exist at room temperature. During the CuInS2 NCs formation, oleylamine not only controls the shape and chemical composition of the CuInS2 NCs, but also influences the phase transition of CuInS2 NCs from chalcopyrite to wurtzite. The proposed synthesis strategy may be used as a general process for the synthesis of metastable wurtzite CuInS2 NCs, and the prepared wurtzite CuInS2 NCs ink may have great potential for absorber layer in solar cells. Crown Copyright (C) 2012 Published by Elsevier B.V. All rights reserved.