Metallic nanoclusters have been attracted considerable attention owing to their unique catalytic and electronic properties as well as their great potential for industrial application. Using molecular dynamics simulations with the Gupta type many-body potential, we investigated the melting of cesium metal nanocluster (Cs-N) with N=55 up to 6750 atoms for the first time. The internal energy, heat capacity, enthalpy, entropy and surface energy of the nanoclusters were calculated at different temperatures. These properties are used to characterize the physical phase and also to determine the melting transition profile of each nanocluster. The melting temperatures of nanoclusters conform to each other and are increased with the cluster size, approaching to the bulk limit for the largest one. The size dependence of the melting temperature is consistent with both experimental results and theories of metal nanoclusters. (C) 2012 Elsevier B.V. All rights reserved.