Childhood parotid swelling has a number of differential diagnosis mostly of inflammatory origin. Pneumoparotitis is an uncommon cause of parotid inflammation. It is caused by an excessive increase of intraoral pressure and secondary passage of air into the Stensen or Stenon duct and its glandular branches. Diagnostic clues can usually be obtained by a directed anamnesis. Ultrasonography (US) and computed tomography are essential diagnostic tools for this condition that has a benign course with spontaneous resolution in most cases. We present four cases of pneumoparotitis diagnosed by US in children 5 to 13 years of age. One of the cases occurred after the child chewed gum and made bubbles for a prolonged timeperiod and the other three after inflating baloons, making bubbles inside a pool and after playing the flute. All cases resolved spontaneously after two days. We suggest to consider pneumoparotitis in the differential diagnosis of parotid swellig in children.