This study investigated the efficacy of ceftriaxone (CTRX) for the treatment of aspiration pneumonia. We compared patients treated with CTRX versus sulbactam/ampicillin (SBT/ABPC). One-to-one propensity score matching was performed to compare the success rates of antibiotic therapy and in-hospital mortality between the groups. Moreover, the duration of antibiotic use, hospital period, and total antibiotic costs were compared among effective patients in the groups. There were 43 and 20 patients in the SBT/ABPC and CTRX groups, respectively. The propensity score matching included 20 patients in each group. There was no significant difference in the success rate of antibiotic therapy (85％ vs 95％, P = 0.62) or in-hospital mortality (25％ vs 5.0％, P = 0.22) between the groups. In addition, there was no significant difference in the duration of antibiotic use (median: 9 days vs 10 days, P = 0.94) or hospitalization period (median: 19 days vs 18 days, P = 0.94) among the effective patients in the groups. However, the total antibiotic costs were significantly lower in the CTRX effective group than the SBT/ABPC effective group (13,731 ± 4,903 yen vs 20.772 ± 6,840 yen, P = 0.001). CTRX may be another choice for antibiotic treatment for patients with aspiration pneumonia when they have no risk of drug-resistant bacteria.