Objective To evaluate the safety and efficacy of Grayson's presurgical nasoalveolar molding (PNAM) technique on nasal and alveolar morphology in infants with unilateral cleft lip and palate (UCLP). Design Systematic review and meta-analysis. Setting : Multicenter international literature across clinical and academic institutions. Patients, Participants Infants with UCLP reported in 21 eligible studies (n = 534), of whom 368 received PNAM. Interventions Presurgical nasoalveolar molding (PNAM) according to the Grayson protocol. Main Outcome Measure(s) : Changes in nasal symmetry (nostril width ratio, columellar angle) and alveolar morphology (alveolar gap dimensions, intertuberosity distance). Results PNAM was performed for an average duration of 96 days with 11 adjustments per patient. Pooled analyses demonstrated significant improvements in nasal symmetry: nostril width ratio decreased from 2.4 (95% CI, 1.7–3.1; I² = 98%) to 1.8 (95% CI, 0.9–2.6; I² = 97%), and the columellar angle increased from 52° (95% CI, 42.0–62.8; I² = 100%) to 70° (95% CI, 59.1–80.6; I² = 98%). Alveolar gap narrowed from 10.7 mm (95% CI, 9.5–11.9; I² = 92%) to 3.9 mm (95% CI, 3.1–4.8; I² = 93%). Intertuberosity distance increased slightly, from 31.3 mm (95% CI, 29.3–33.3; I² = 95%) to 31.8 mm (95% CI, 28.9–34.8; I² = 98%). Conclusions Grayson's PNAM appears to improve nasal and alveolar morphology in infants with UCLP prior to definitive surgery. Standardized outcome measures and long-term prospective studies are needed to confirm these findings and refine clinical protocols.