WHO guidelines recommend the use of antibiotics for all cases of pneumonia in children, despite the majority being caused by viruses. We performed a systematic review and meta-analysis to determine which children aged 2-59 months with WHO-defined fast breathing pneumonia, if any, can be safely treated without antibiotics.We systematically searched medical databases for articles published in the last 20 years. We included both observational and interventional studies that compared antibiotics to no antibiotics in children aged 2-59 months diagnosed with fast breathing pneumonia in low- and middle-income countries (LMICs). We screened articles according to specified inclusion and exclusion criteria, and assessed for risk of bias using the Effective Public Health Practice Project (EPHPP) framework. Overall, we included 13 studies in this review. We performed a meta-analysis of four included studies comparing amoxicillin to placebo.Most children with fast breathing pneumonia will have a good outcome, regardless of whether or not they are treated with antibiotics. Meta-analysis of four RCTs comparing amoxicillin to placebo for children with pneumonia showed higher risk of treatment failure in the placebo group (odds ratio OR 1.40, 95% confidence interval CI = 1.00-1.96). We did not identify any child pneumonia subgroups in whom antibiotics can be safely omitted. Limited data suggest that infants with clinically-diagnosed bronchiolitis are a particular low-mortality group who may be safely treated without antibiotics in some contexts.Children with WHO-defined fast breathing pneumonia in LMICs should continue to be treated with antibiotics. Future studies should seek to identify which children stand to benefit most from antibiotic therapy, and identify those in whom antibiotics may not be required, and in which circumstances.