CONTEXT The optimal duration of antibiotic treatment of children with community-acquired pneumonia (CAP) remains unclear. OBJECTIVES This study aimed to compare the efficacy and safety of shorter versus longer duration of antibiotic treatment of children with CAP. DATA SOURCES We searched Medline, Embase, CENTRAL, and CINAHL. STUDY SELECTION Randomized clinical trials comparing shorter (≤5 days) with longer duration antibiotic treatments in children with CAP. DATA EXTRACTION Paired reviewers independently extracted data and we performed random-effects meta-analyses to summarize the evidence. RESULTS Sixteen trials with 12 774 patients, treated as outpatients with oral antibiotics, proved eligible. There are probably no substantial differences between shorter-duration and longer-duration antibiotics in clinical cure (odds ratio 1.01, 95% confidence interval [CI] 0.87 to 1.17; risk difference [RD] 0.1%; moderate certainty), treatment failure (relative risk [RR] 1.06, 95% CI 0.93 to 1.21; RD 0.3%; moderate certainty), and relapse (RR 1.12, 95% CI 0.92 to 1.35; RD 0.5%; moderate certainty). Compared with longer-duration antibiotics, shorter-duration antibiotics do not appreciably increase mortality (RD 0.0%, 95% CI −0.2 to 0.1; high certainty), and probably have little or no impact on the need for change in antibiotics (RR 1.03, 95% CI 0.72 to 1.47; RD 0.2%; moderate certainty), need for hospitalization (RD −0.2%, 95% CI −0.9 to 0.5; moderate certainty), and severe adverse events (RD 0.0%, 95% CI −0.2 to 0.2; moderate certainty). LIMITATIONS For some outcomes, evidence was lacking. CONCLUSIONS Duration of antibiotic therapy likely makes no important difference in patient-important outcomes. Healthcare workers should prioritize the use of shorter-duration antibiotics for children with CAP treated as outpatients with oral antibiotics.