Abstract: The issue of heat death is reanalysed on the basis of the standard model of cosmology. The evolution of the universe consists of both microscopic and macroscopic clustering processes. From the point of view of physics, these clustering processes are mainly dynamical rather than thermodynamical. The dynamical process may destroy the thermodynamical equilibrium, while thermodynamics tends to retrieve the equilibrium. All the well known laws of physics play their roles during evolution. As a result, the entropy of the universe is always increasing. In this sense Clausius is right. But the heat death of the universe, as predicted by Clausius, will not be reached, since some component particles will be decoupled during the evolution.