A total of 228 accessions of cassava germplasm were collected from 19 regions of China and abroad. 22 morphological and agronomic characters including 15 descriptive morphological characters of stems and roots, as well as 7 quantitative characters related to yield, were evaluated. The aim of the study was to understand the genetic diversity of the germplasm and provide a theoretical reference for germplasm innovation, as well as introduction and selection of parents for breeding. Results showed that, the frequence and distribution of morphological characters of cassava resources from China and abroad are uniform. The majority are the types of open-branches with three bifurcation, 30 degrees to 45 degrees of branching angle, light-green endothelium, white fleshy roots with rough and brown epidermis, and yellow endothelium. Diversity indexes showed 1.895-2.073 and 0.435-1.889 for quantitative and morphological traits respectively. Broad range of variability from 8.91-44.60% of quantitative characters was observed among the 228 accessions. Root diameter of China resources was significantly higher than that of foreign resources, while dry matter content of the foreign resources was significantly higher than that of China resources, indicated that the root diameter and the dry matter content of domestic and foreign resources has obvious genetic differences. It was possible to choose high yield and good quality varieties from these germplasms. Two step cluster analysis obviously divided the resources into two similatity groups I and II. Group I is composed of open-branch types with medium to large branching angle, irregular population and thick stem, high tubers yield; Group II is composed of compact and upright plant types with small branching angle, regular population, thin stem and high dry matter content in the tuber. Future breeding work should integrate phenotypic differences of the parents into progenies by combination of elite characters to achieve expected objectives in breeding programs.