Background Adverse drug events associated with medication errors (MEs) are three times higher in children than in adults. To reduce MEs in children, studies have reported the advantage of clinical pharmacist implementations, but a thorough overview of dedicated activities has not yet been clearly described. Objectives The objective of this systematic review was to establish an international overview of clinical pharmacy services (CPS) practiced by pharmacists for pediatric inpatients. Methods Two databases were searched for original articles published from January 2000 to 2019. Additionally, a manual hand search was conducted. Studies dealing with CPS performed by pharmacists for pediatric inpatients were included. General and geographical data, method, design, and population characteristics of studies were extracted. The primary outcome was to quantify and describe pediatric CPS. Secondary outcomes were to quantify the presence of an age range analysis and impact evaluation. Six validated checklists were used to assess the quality of studies included. Results After a full-text review, 42 studies were included. Among the 15 CPS reported, pharmaceutical interventions for prescriptions, medication reconciliation, interactions with medical and paramedical teams, ward round participation, and patient therapeutic education were the most frequently detailed. Only eight studies considered age interpretation. The principal limitation was the heterogeneity of studies. Conclusion This work provides a basis for harmonizing the deployment of pediatric CPS in hospital to improve patient safety. Because pharmacists’ time resources are limited, CPS should be prioritized according to hospital population, service organization, and needs evaluation.