Abstract: In this paper, a coarse-grained reconfigurable computing unit (RCU) is designed for the heterogeneous multi-core system (HMCS) which is applied to high density computing field. As a reconfigurable computing unit, RCU can achieve a variety of functions and work in different modes. The architecture of RCU is also optimized for some common complex algorithms, such as matrix calculation, FFT and etc. At last, the hardware prototype of RCU is implemented on the FPGA and the experimental results show that the performance has achieved the performance requirements.