Diaper dermatitis is a common disorder. Coriandrum sativum is a herbal remedy with anti-inflammatory, analgesic, anti-microbial and anti-oxidant activities effects. In this nonrandomised clinical trial which was performed on 58 infants with diaper dermatitis referred to Faghihi Hospital, Shiraz University of Medical Sciences, the efficacy and safety of topical Coriandrum extract cream is compared with hydrocortisone ointment. Coriandrum sativum extract cream was administered for 37 (intervention group) and hydrocortisone 1% ointment for 21 (control group) patients. Patients were examined on days 3 and 10. Chi-square test was applied for statistical analysis. The results demonstrated a statistically significant difference in the cure rate (20 (54.1%) for the intervention group versus 19 (90.5%) for the control group) (P-value = 0.005) and side effects (10 (27%) for the intervention group versus 0 (0%) for control group) (P-value = 0.009) both in favor of hydrocortisone. This trial failed to confirm the efficacy of Coriandrum sativum in the treatment of diaper dermatitis; however, it seems that if soothing compounds are used in combination with Coriandrum sativum to reduce the mild irritation, Coriandrum extract can be an alternative treatment for diaper dermatitis.