Intraocular pressure (IOP) can increase with postural changes, which can cause ocular complications. Neck extension is commonly used during palatoplasty to improve surgical angulation. This study evaluates whether neck extension affects IOP during palatoplasty. In this prospective observational study, IOP was measured using a rebound tonometer at four specific time points: T1, 10 min after anaesthesia while in the supine position; T2, 5 min after neck extension; T3, at completion of palatoplasty with neck extended; and T4, 5 min after returning to the supine position. The primary outcome was the IOP at T2, and the secondary outcomes were the IOPs at T3 and T4. Haemodynamic and respiratory variables were also measured at each time point. Thirty-seven patients were included. IOP at T2 was significantly higher than at T1 (15.8 ± 3.4 mmHg vs 10.5 ± 2.8 mmHg, P < 0.001), and IOPs at T3 and T4 were also significantly higher than at T1 (T3 vs T1: 18.9 ± 3.6 mmHg vs 10.5 ± 2.8 mmHg, P < 0.001; T4 vs T1: 13.3 ± 3.7 mmHg vs 10.5 ± 2.8 mmHg, P < 0.001). However, no significant differences were observed for the haemodynamic and respiratory variables at any time point. Our findings indicate that the intraoperative neck extension position during palatoplasty significantly increases IOP in paediatric cleft palate patients undergoing a palatoplasty.