The clinical efficacy and safety of clarithromycin (CAM) and cefdinir (CFDN) were evaluated in 65 pediatric outpatients with group A beta-hemolytic streptococcal tonsillopharyngitis. Treatment was "effective" or better in 26 (78.8%) children receiving CAM and in 27 (87.1%) receiving CFDN based on antigen clearance and the "Criteria for Evaluation in Clinical Trials of Antibacterial Agents in Children" proposed by Japan Society of Chemotherapy (p = NS). The causative organisms were eradicated in 94.7% and 93.8% of subjects in the CAM and CFDN groups, respectively (p = NS). Adverse drug reactions were limited to moderate diarrhea in one patient in each group, and subsided during treatment. Causative organisms exhibited good susceptibility to CAM and CFDN. These results suggest excellent efficacy, safety and usefulness of CAM and CFDN in the treatment of group A beta-hemolytic streptococcal tonsillopharyngitsis in children.