Persistent pulmonary hypertension of the newborn (PPHN) is a life threatening condition associated with an increased risk of neurological impairment. Magnesium sulfate (MgSO_{4}) is an alternative and low cost treatment for PPHN. Despite more appropriate and available therapies MgSO_{4} is still widely used, especially in developing countries, but long-term follow-up is unknown. In a retrospective controlled study we evaluated whether MgSO_{4} therapy for PPHN was associated with increased neuro-developmental impairments at follow-up, as compared to a control group. Population consisted of 33 infants treated for PPHN with MgSO_{4}only (study group) and 32 healthy term infants (control group). Extensive neuro-developmental follow-up examination was performed at 18 months and 5 years of age. Rate of major impairments and minor impairments were evaluated and compared to the literature. The rates of major impairments in the study group at 18 months and 5 years were 6% and 11.4%, respectively, and 0% at both ages in the control group. The rates of minor impairments at the same ages were 3% and 26.9% for the study group, and 0% and 26.1% for the control group. Mean developmental quotients at 18 months were 106.6 (SD 1.6) in the study group and 118.3 (SD 1.0) in the control group (p<0.001). General intellectual index at preschool age was not significantly different between the two groups. Treatment with MgSO_{4} does not increase the rate of disability, as compared to other treatments for PPHN.