Abstract: On the basis of analysing for Darwinian processes and irreversible thermodynamic processes in real nature and society evolution, this paper proposes and implements a Darwin and "Boltzmann mixed strategy, a new and effective general stochastic approach, for optimization of discrete complex systems which has an extensive theoretical and applicational background. The results of analyses and evaluations show that the strategy is efficient and superior to simulated annealing algorithm. Undoubtedly, the research works of the paper will provide a new way of analysing and solving for optimization of discrete complex systems.