Learner modeling still the object of very active research in the technology-enhanced learning system. It makes it possible to represent a complete description of the learner. In this paper, we have proposed a new learner modeling approach which is independent on the learning system and dependent on the learning context. The proposed model involved four information categories: Personal data describing the general information about the learner; Cognitive data representing the learner performances and knowledge; Activity data providing details about learner activities during the learning process. Finally, contextual data presenting a description about learner context such as location, device, accessibility, connectivity, etc. To ensure a better representation of these characteristics, we have proposed an ontology-based learner model in order to benefit of advantages gained from the use of ontological technology, like extensibility, usability, exchanging information, inferring new knowledge by reasoning on an existing one.