This paper describes parallel simulation techniques for the discrete element method (DEM) on multi-core processors.Recently,multi-core CPU and GPU processors have attracted much attention in accelerating computer simulations in various fields.We propose a new algorithm for multi-thread parallel computation of DEM,which makes effective use of the available memory and accelerates the computation.This study shows that memory usage is drastically reduced by using this algorithm.To show the practical use of DEM in industry,a large-scale powder system is simulated with a complicated drive unit.We compared the performance of the simulation between the latest GPU and CPU processors with optimized programs for each processor.The results show that the difference in performance is not substantial when using either GPUs or CPUs with a multi-thread parallel algorithm.In addition,DEM algorithm is shown to have high scalability in a multi-thread parallel computation on a CPU.