Acute isolated velopharyngeal insufficiency (VPI) is a clinical entity mainly reported in children. We undertook a systematic review in order to better characterize its features. Following a Medline search (1960-2012), the authors reviewed and analyzed the cases of acute VPI in children; 36 cases were found. The most common presenting features were hypernasal speech (97 %), nasal reflux (73 %), and dysphagia (49 %). 73 % of the children were males and 27 % females, of 8.9 ± 2.5 years. In all the cases the VPI was unilateral. One quarter of the children had a recent episode of febrile illness and 11 % of the children had an identified infection at the time of presentation (HAV, parvovirus B19, measles, and Coxsackie virus). No associated cause was found in the other cases. All cases resolved completely (67 %) or partially (33 %) without any treatment (89 %) or with prednisolone (11 %). Acute VPI represents a separate entity within the spectrum of VPI and it is a benign self-limiting disorder. The cause remains undetermined but an infectious disorder may play a role at least in some cases. Follow-up is mandatory in order to eliminate progressive conditions such as brainstem neoplasms or inflammatory diseases.