Marfan syndrome (MFS) is an autosomal dominant and multisystemic disorder affecting the connective tissues. Patients with MFS may exhibit characteristic oral features including maxillary protrusion, high palate, crowded teeth, and fragility of the temporomandibular joint. Periodontal manifestations may include a higher prevalence of gingivitis and/or periodontitis owing to the high concentration of elastic fibres in the periodontal ligament. This case report describes the management of gingival enlargement associated with MFS. The patient was successfully managed with non-surgical and surgical periodontal therapy. In patients with oral manifestations of systemic disorders, patient motivation and effective treatment planning are able to achieve the optimum periodontal and oral health outcomes.