Background: Corticosteroids are potent medications used to treat many inflammatory conditions in paediatric neurology practice. Although corticosteroids are beneficial, their adverse effects may be numerous and varied. As parents are the primary caregivers of paediatric patients, assessing their awareness is important. Methods: To determine the parental awareness on the adverse effects of corticosteroid therapy in Paediatric Neurology Patients in the Neurology Unit at the Lady Ridgeway Hospital, Colombo, Sri Lanka, this descriptive cross-sectional study, looked at 300 parents of paediatric neurology patients on long-term corticosteroid therapy. Parents volunteered for the study and signed with informed consent. Ethical approval was obtained from the Ethics Review Committee of the same hospital. Data were collected using content validated, pre-tested self-administered questionnaire during January to March 2020. Results: Of the total parents, the majority were mothers (87%, n=262) and more than 70% (n=211) of them completed their secondary education. Findings demonstrated that parents had average awareness about adverse effects of long-term steroid therapy including child's susceptibility to infections (69.0%, n=207), increase blood glucose levels (69.7%, n=209), moon face (60.3%. n=181), central obesity (60.3%, n=181), increase blood pressure levels (58.0%, n=174) and (irritability 50.3%, n=151) while poor awareness on adverse effects include buffalo humps (26.7%, n=80) increase fracture tendency (24.3%, n=73), tarry colour stools (24.3%, n=73), vision impairment (24.0%, n=72), glaucoma (17.3%, n=52), cataract (16.0%, n=48 ) and delayed wound healing (23.0%, n=69). According to the findings, overall mean (SD) knowledge percentage on parental awareness of adverse effects was found to be low (38.24 ± 20.57). Conclusion Since parental awareness of the adverse effects of long-term corticosteroid therapy is inconsistent, special attention is needed to plan and implement appropriate awareness sessions.