Aims: Humans have long used plant extracts to relieve the symptoms of various diseases. This study aimed to investigate the efficacy of Eucalyptus in treating upper respiratory infections in children aged 5 to 15 years. Methods & Materials: A case-control study was conducted on the children aged 5-15 years who were referred to the clinics of Zahedan Medical University, Zahedan City, Iran, in 2018-19. A total of 208 children were examined in two groups: case patients diagnosed with an acute upper respiratory infection and control patients matched to the case group. To prepare Eucalyptus incense, 2 drops of Eucalyptus oil were mixed in 750 mL of hot water. In the case group, Eucalyptus incense was prescribed every 3 hours for 15 minutes for 3 days. Also, in the control group, just water vapor was prescribed. Finally, the patients of both groups were evaluated by the researcher on the third day, and the information was entered into the Canadian Acute Respiratory Illness Flu Scale (CARIFS) questionnaire. Then the data were analyzed in SPSS v. 22. Findings: The current study showed that Eucalyptus fumigation significantly improved patients’ symptoms in all upper respiratory tract infections such as cold (P=0.016), rhinitis (P=0.032), sinusitis (P=0.028), pharyngitis (P=0.043), otitis (P=0.046) and laryngotracheitis (P=0.014). Conclusion: Eucalyptus incense generally causes clinical improvement in children with upper respiratory tract infections. As a result, it is possible to use this substance with other treatments according to the patients’ clinical conditions.