Data and information about Indonesian genetic resources and traditional knowledge, especially the current data on medicinal plants is not managed optimally yet. The data and information is still scattered which if there is no integrated management action done, the data and information might be lost. One effort to integrate the data about medicinal plants is by building the ontology. This research develops a socio-technical model in ontology engineering by taking a case study of the development of Indonesian medicinal plants ontology. The ontology will support the development of applications based on Indonesian medicinal plants. Sources of data in this ontology considered from five aspects such as pharmacology, health practitioners, plant taxonomy, plant cultivation, and conservation of rare medicinal plants. The results of this study initiate the establishment of Indonesian medicinal plants ontology that is needed by various parties and support protection and utilization of genetic resources in Indonesia optimally. Validation of the ontology is carried out through a functionality of list data of competency questions executed on a semantic web application.