Introduction. Cleft lip and palate are congenital abnormalities that caused by many factors. Dental abnormalities in patients with cleft lip and palate were begun during eruption phase such as caries, crown and root deformity, abnormalities number of teeth and the relationship between maxilla and mandibula. Interdisciplinary treatment are required to gain optimum results for patients with clefts. Apexification followed by proper restoration are needed to correct a necrotic tooth with an open apex in cleft lip and palate patients. The aim of this paper is to report treatment of necrotic tooth with open apex in a cleft lip and palate patient. Case report. A 23-year-old female patient was referred to Department of Conservative Dentistry by orthodontist to treat her central incisor maxilla. The patient had a history of cleft lip and palate and had been wearing orthodontic braces for 3 years. Tooth 11 was asymptomatic, periapical radiograph showed radiolucent area on the apical region with open apex. The diagnosis was necrotic pulp with open apex. Apexification treatment using Mineral Trioxide Aggregate followed by fiber post and indirect composite crown were carried out. Indirect composite crown were made on tooth 21 for an aesthetic purpose. The patient returned for follow-up after 6 months with no complaints. Both clinical finding and radiograph show normal tissues and the tooth function normally. Conclusion. The apexification followed by indirect composite crown are the right treatment for treating maxillary central necrotic incisor with open apex in the cleft lip and palate patient.