Motivation: To identify the genetic susceptibility to human disease is the central task for the medical genetics researchers; however, to distinguish the true susceptibility factors remains far less satisfaction. Considering the complex and unstructured information on this topic, an ontology is important to explicit the concepts and their relationships in the domain of the genetic susceptible factors to common disease. Here by using Diabetes Mellitus as an example,we developed an Ontology of Genetic Susceptibility to Common Disease (OGSCD). Results:??The core conception was primarily summarized, then we half adopted conceptions from BFO to develop the ontology starting from the top level. A hybrid of middle-out and top-down approach was conducted for the construction of OGSCD. By using Prot?ge-OWL editor, we developed the ontology which represents the knowledge of the susceptibility genetic factors to common disease.