Objective The purpose of this study was to describe a detailed investigation of craniofacial and dental characteristics in a group of Brazilian Rubinstein–Taybi syndrome (RSTS) patients. Methods and results Thirteen RSTS patients treated in a special care dental clinic after 10 years were studied. Panoramic radiographs were obtained from all patients, and cephalometric analysis was performed in eight patients. Five male and eight white female patients with a median age of 11.7 years were analyzed. All the RSTS patients were mouth breathers and presented malocclusion, transverse hypoplastic maxilla, nine subjects (9/13; 69.2%) had posterior crossbite, and eight (61.53%) exhibited talon cusps. Most patients presented class II skeletal pattern and were brachycephalic. Regarding systemic disorders, one patient (7.69%) reported seizure episodes during childhood, and four patients (30.76%) presented heart valve disorders. All patients presented reduced attention span, low intolerance to dental interventions, impulsiveness, and irritability. Conclusions Since RSTS exhibits oral and skeletal changes, early dental treatment is essential for these patients. Dentists must be aware of medical problems related to heart disease and persist in conditioning techniques to obtain cooperation and avoid dental care under general anesthesia.