We present both experimental and theoretical study of thermally induced morphological transition of silver nanofractals.Experimentally, those nanofractals formed from deposition and diffusion of preformed silver clusters on cleaved graphite surfaces exhibit dendritic morphologies that are highly sensitive to any perturbation, particularly caused by temperature. We analyze and characterize the morphological transition both in time and temperature using the recently developed Monte Carlo simulation approach for the description of nanofractal dynamics and compare the obtained results with the corresponding experimental data. The reported results reveal essential and general features of dynamical systems having dendritic shape.