Background and Objectives: Steroids have strong anti-inflammatory, anti-edema, and antipyretic effects. Since there are few studies on the use of steroids in the treatment of peritonsillar abscess in Korea, we aimed at this study to investigate the effects of steroids along with antibiotics in the treatment of peritonsillar abscess.Subjects and Method A retrospective study was conducted on 75 patients who were admitted from 2014 to 2019. Between 2014 and 2017, only antibiotics were administrated after incisional drainage (no-use group), but between 2018 and 2019, antibiotics and adjunctive steroids were administrated after incisional drainage (steroids group). Symptoms of patients, blood tests, diets available, and hospitalization period were compared between the two groups. Results: The length of hospital stay for the steroids group (n=24) and the no-use group (n=51) was 4.2±1.3 days and of 5.1±1.8 days (p=0.046), respectively, showing significantly shortened time for the steroids group. The rate of change in 48-hour C-reactive protein was 53.3% and 20% for the steroid group and no-use group (p=0.013), respectively. However, there was no differences between the two groups in the rate of change in body temperature at 12 hours of treatment, the diet available at 12 hours, and rate of change in the number of white blood cells after 48 hours of treatment. Conclusion Adjunctive steroids for peritonsillar abscess can be a useful treatment that shows rapid improvement of symptoms and C-reactive protein, and shorter hospitalization periods.