Knowledge-based technology with complete access to useful information is vital to support decision-making and solve complex problems in many areas such as management, medical, business, education and others. However, the domain of specific learning disabilities still suffers from the lack of explicit representation of knowledge and data modelling format through explicit format and standards such as RDF and OWL, which limits the effective sharing between experts and general users. Therefore, this article presents a novel domain ontology, called ONT-SLD, to formally conceptualize essential elements and rules, covering the characteristics of specific learning disabilities student and educational activities. During the ontology building, applicable standards and regulations have been extensively adopted. The proposed ontology model is evaluated in a real-world case to early identify a student with learning disabilities and recommend appropriate educational activities. Taxonomy evaluation is conducted using SPARQL to show the ontological model is able to detect any semantic conflicts. The future work includes the extension of ONT-SLD to other types of special education so that it can contribute to a broader range of applications in the special education environment.