Over the past several years a number of reports about chemical synthesis of colloidal I-III-VI2 nanocrystals (NCs), particularly CuInS2 (CIS), has drastically increased [1,2] due to their attractive electronic and optical properties and absence of toxic elements such as Cd that diminishes all the merits of II-VI compound NCs. Moreover, I-III-VI2 NC synthesis can utilize lower processing temperatures than bulk synthesis methods and device fabrication with NCs can benefit from roll to roll processing and solution-phase processing such as printing. The wurtzite phase, which is uncommon to CIS compounds, recently became accessible via colloidal synthesis [2,3] and allows, in addition to above mentioned merits of CIS compounds, flexibility of stoichiometry due to the copper and indium randomly sharing the cationic sublattice. This is beneficial for device fabrication because it provides the ability to tune the Fermi energy over a wide range. Raman spectroscopy is widely used for identification of the crystal structure, non-stoichiometry and secondary phases in IIIIVI2 compounds [4]. Here we report the results of a Raman scattering study of lattice vibrations in CuInS2 nanocrystals of wurtzite modification. Based on a comparison with the experimental data of chalcopyrite CuInS2 crystals and the results of first principle calculations, a close similarity of the spectra of wurtzite nanocrystals and chalcopyrite is established. Possible effects of the cation sublattice ordering are discussed. The excitation wavelength- and polarization-dependent measurements are used to confirm the nature of certain vibrational modes.