Objective: To compare the rate of serious adverse perinatal outcomes of term labour between private and public maternity hospitals in Australia. Design, setting and participants: A population-based study of 789240 term singleton births in public and private hospitals in 2001-2004, using data from the National Perinatal Data Collection. Main outcome measures: Third- and fourth-degree perineal injury, requirement for high level of neonatal resuscitation, Apgar score < 7 at 5 minutes, admission to neonatal intensive care unit or special care nursery, and perinatal death. Results: 31.4% of the term singleton births occurred in private hospitals. After adjusting for maternal age, Indigenous status, parity, smoking status, diabetes, hypertension, remoteness of usual residence, and method of birth, the rates of all adverse outcomes studied were higher for public hospital births. For women, the adjusted odds ratio (AOR) for third- or fourth-degree perineal injury was 2.28 (95% Cl, 2.16-2.40). For babies, the odds of a high level of resuscitation (AOR, 2.37; 95% Cl, 2.17-2.59), low Apgar score (AOR, 1.75; 95% Cl, 1.65-1.84), intensive care requirement (AOR, 1.48; 95% Cl, 1.45-1.51) and perinatal death (AOR, 2.02; 95% Cl, 1.78-2.29) were all higher in public hospitals. Conclusion: For women delivering a single baby at term in Australia, the prevalence of adverse perinatal outcomes is higher in public hospitals than in private hospitals.