-- A new Dominant Color Structure Descriptor (DCSD) is proposed in this paper. It is designed to provide an efficient way to represent both color and spatial structure information with single compact descriptor. The descriptor combines the compactness of Dominant Color Descriptor (DCD) and the retrieval accuracy of Color Structure Descriptor (CSD) to enhance the retrieval performance in a highly efficient manner. The feature extraction and similarity measure of the descriptor are designed to address the problems of the existing descriptors while utilize the advantages of them. Experimental results show that DCSD has a significant improvement on both retrieval performance and descriptor size over DCD. An eight-color DCSD (DCSD 8) gives an Averaged Normalized Modified Retrieval Rate (ANMRR) of 0.0993 using MPEG-7 common color dataset, outperforming compact configurations of Scalable Color Descriptor and Color Structure Descriptor with smaller descriptor size. Keywords -- Content Based Im...