Abstract: Objectives: To analyse prescription of antibodies in emergency dental service according to antibiotic type, working diagnosis, patient visit time and patient demographic characteristics. Additionally, prescription practices among individual dentists were analysed. Methods: The data in this retrospective cohort study were collected from electronic medical records and analyzed using descriptive statistics. Statistical analyses were conducted using the chi-square test and the Z-test with post-hoc Bonferroni adjustment (α =0.05). Results: The study covered 20,879 patient visits during a 1.5-year period (from 1 June 2015 to 1 December 2016). Antibiotics were prescribed in 10,188 (48.8%) visits. In 6,202 (29.7%) visits, no dental treatment was performed and only an antibiotic was prescribed. The antibiotics most frequently prescribed were from the penicillin group and also contained clavulanic acid (70.5%); the second most frequently prescribed antibiotic was clindamycin (15.0%). The most common diagnoses for which an antibiotic was prescribed were acute apical abscess, pericoronitis and retained root; for these diagnoses, an antibiotic was prescribed in 79.8%, 64.3% and 63.3% of visits, respectively. Prescription of an antibiotic was significantly more frequent during Sundays and holidays (55.6% of visits) than during working days (33.2% of visits). Prescription of an antibiotic increased from the age of 1 towards the age of 75 and decreased thereafter. Female dentists prescribed antibiotics slightly but significantly (P < 0.001) more frequently than male dentists (50.8% and 46.8% of visits, respectively). High heterogeneity was observed among dentists regarding their criteria for prescribing antibiotics; individual dentists prescribed antibiotics in 15.0%–72.1% of the total number of visits. Conclusion: Multiple possible issues in the prescription of antibiotics were observed, ranging from administration for inappropriate indications to noncritical and excessive prescription.