It is of practical importance to predict the melting point of metal nanowires in a confined environment. Based on molecular dynamics (MD) simulations, a universal model unravelling the relationship between the melting point of a metal nanowire in nanoconfinement and its cap surface curvature has been developed for the first time. The results have demonstrated that both the interaction strength between the nanowire and the nanoconfinement and the diameter of nanoconfinement dramatically affect the melting point of the embedded nanowire. These phenomena can be further expressed in a mathematical formula directly describing the curvature-dependent melting point. It is also found that the melting feature of the metal nanowire under weak interaction is quite different from that under strong interaction. Furthermore, the melting point of the free cluster can also be predicted using this model. Our findings have provided a direct way to analyze the melting point via the observed morphology of the metal nanoparticle.