OBJECTIVE: Acute pulmonary edema associated with ritodrine hydrochloride is a rare, life-threatening complication, and dose and duration of ritodrine use are closely associated with this pathology. We report a case of acute pulmonary edema associated with short-duration infusion of ritodrine hydrochloride in a patient with pectus excavatum as an underlying factor. CASE REPORT: A 30-year-old healthy pregnant woman was treated with oral ritodrine for tocolysis between 31 and 35 weeks of pregnancy. At 36 weeks of gestation, she went into preterm labor, with premature rupture of the membrane and breech presentation, and received an infusion of ritodrine hydrochloride for a few hours. Although she was normotensive until labor onset, mild hypertension and proteinuria were recognized. Intraoperatively, a funnel-chest deformity was observed, and she developed postoperative pulmonary edema associated with dyspnea and wet cough and confirmed on chest radiography and arterial gas analysis, and recovered with supportive care. CONCLUSION: Small-dose infusion of ritodrine hydrochloride might cause pulmonary edema in patients with underlying medical problems, including pectus excavatum.