The Holy Quran has rules that the reader must learn so that he can read the Qur'an correctly (Tajweed).The objective of this research is to design an ontology for some of Tajweed (Articulations Points of the Letters, Un Vowel Noon and Tanween) to support the learning of this part of Tajweed and to facilitate the sharing of knowledge with the other Holy Quran applications. In order to achieve this goal, the researchers adopted the applied approach using protégé framework with OWL to the provisions build the Ontology. The provisions of Quran Tajweed Ontology (Articulations Points of the Letters, Un Vowel Noon and Tanween) use knowledge representation to define the key concepts in Un Vowel Noon and Tanween (Clearness, Merge, Hiding, Change) and The Letters Articulations, and show the relationships between these concepts and its properties. The fundamental concepts in the ontology are based on the knowledge extracting from the Books of Tajweed, and some verses of the Holy Quran to infer the Provisions. The designed ontology can retrieves information about Articulations Points of the Letters, Un Vowel Noon and Tanween. Furthermore, it can be shared and reused in applications related to Holy Quran Tajweed
