Gastroesophageal reflux disease (GERD) is a relevant problem in first months of life and its early diagnosis and its appropriate therapy represent a real challenge for neonatologists.Multichannel Intraluminal Impedance associated with esophageal pH-monitoring (MII/pH) has been recently introduced to study GERD in infants. This technique, which is safe and with a good compliance, presents an elevated accuracy in identifying refluxes independently from their pH. The main aim of this review is to analyse data in literature on the use of MII/pH in neonates.We have considered recent studies published in PubMed in which MII is used in neonates and infants with GER: 26 studies focus on GER physiopathology and on the advantages of using MII in addition to pH-monitoring, 13 on symptoms associated with refluxes (in particular cardio-respiratory events and apnoeas) and 13 on therapy (5 on body position, 3 on thickened formulas, 1 on fortified milk and 4 on drugs).We underline the role of MII/pH in studying GERD in neonates, in which non acid-refluxes result prevalent, because of the buffering effects of milk, and in which the majority of symptoms arerelated to non-acid or weakly-acid GER. MII/pH can be considered a good technique even in the evaluation of the temporal relation between refluxes and symptoms and in the analysis of the benefits obtained by pharmacological and non-pharmacological therapy.The increasing application of MII/pH can help neonatologists to comprehend GER physiopathology, to diagnose GER and GERD and to treat better its symptoms in first months of life.