Introduction: Subcutaneous facial emphysema in children is uncommon and is typically associated with trauma, dental procedures or infection. Retrograde air insufflation through Stensen’s duct following a forceful Valsalva manoeuvre is a rare nontraumatic mechanism. Early recognition is essential to prevent unnecessary investigations and exclude serious complications such as pneumomediastinum. Case presentation: A 12-year-old male with attention deficit hyperactivity disorder (ADHD) presented with sudden-onset, painless bilateral facial swelling and trismus. There were similar three episodes diagnosed to be subcutaneous emphysema, managed conservatively and the exact cause was not identified. There was no history of trauma, dental intervention or infection. Examination revealed non-tender swelling over the parotid and periauricular regions. Plain Xray showed air tracking over the parotid gland. Computed tomography confirmed emphysema surrounding the parotid glands, within the parotid duct without mediastinal extension. Repeated questioning child admitted that he has forcefully blowed against a pipe with apurpose of making sound just prior to the onset of the symptoms. Conservative management, resulted in complete resolution within 72 hours. Conclusion: Valsalva-induced retrograde air insufflation via the parotid duct is a rare but benign cause of paediatric facial emphysema. Cross-sectional imaging confirms diagnosis and excludes life-threatening complications. Behavioural counselling is essential to prevent recurrence.