To evaluate the performance of a novel 3D-printed customized nasal mask on patient satisfaction and compliance to continuous positive airway pressure (CPAP) therapy for obstructive sleep apnea (OSA). Patients prescribed CPAP therapy with suboptimal CPAP compliance using a conventional CPAP mask (<70% of nights with ≥4 hours per night over 4 weeks) were recruited from the sleep investigation unit of a tertiary hospital. Patients underwent a 3D-facial mapping procedure to have a novel 3D-printed customized nasal mask fabricated which was trialed four weeks. CPAP compliance data download of the same period was conducted with their pre-existing conventional mask and customized mask. Questionnaires assessing symptoms of OSA and mask-related side-effects were administered before and after the trial of the customized mask. Thirty patients (twenty-two males and eight females, age 63.3 ± 12.5 years, BMI 31.7 ± 5.2 kg/m2, apnea-hypopnea index 37.3 ± 21.9 events/h [mean ± standard deviation]) were studied. CPAP was used in a greater proportion of nights with the customized mask (85.7 [66.1, 98.2]% versus 63.2 [13.1, 96.8]%, P=0.009) compared to the conventional mask. Hourly CPAP usage was higher with the customized mask (3.8 [2.7, 5.8] hours versus 2.4 [0.3, 5.0] hours, P=0.016) compared to a conventional mask. Patients preferred the customized mask (P=0.008) and reported less mask-related side effects. The novel 3D-printed customized mask improved CPAP usage in patients with suboptimal CPAP compliance. Customized CPAP masks may be a suitable option for patients experiencing poor CPAP compliance from mask-related side effects. Registry: ANZCTR; Title: Conventional vs custom made nasal Continuous Positive Airway Pressure (CPAP) mask for treatment of Obstructive Sleep Apnoea: Pilot study A; Identifier: ACTRN12621001301853; URL: https://anzctr.org.au/Trial/Registration/TrialReview.aspx?id=382142.