Wireless sensor networks (WSNs) provide various environment data in the real-world, and also WSNs's middleware is able to offer field data in real-time by user queries. For materialization of the future ubiquitous computing which enables networking with things at anytime, anywhere and any-devices, WSNs occupy the important position with RFID technologies, and it has evolved and advanced currently. This paper proposes a service-oriented sensor ontology which enables service-oriented services in future ubiquitous computing. Taking reuse of ontology into consideration, ServiceProperty, LocationProperty and PhysicalProperty classes were derived from Geography Markup Language (GML), Sensor Web Enablement (SWE), SensorML and Suggested Upper Merged Ontology (SUMO) and OntoSensor ontology, and its properties and constraints were also defined newly as service-oriented service. We presented the validation and consistency check of the proposed ontology using Prot?g? 3.3.1 and RACER 1.9.0, respectively, and indicated the results of service query which used the SPARQL query language.