Urinary tract infection (UTI) is an infection that can occur in any area of the urinary tract which is characterized by a positive urine culture (U/C). The risk of UTI following cesarean section (CS) increases due to procedures such as catheterization. In vitro studies have demonstrated the effect of Rosa canina fruit in preventing Escherichia coli growth. This study was conducted to determine the effect of R. canina fruit in preventing the incidence of UTI in women following CS. This triple-blind randomized clinical trial was conducted in 2016 on 400 women following CS with negative U/C in Alzahra and Taleghani educational hospitals in the city of Tabriz-Iran. Participants were assigned into two groups of 200 women using block randomization. Each group received a twice daily dose of 500 mg capsules containing R. canina or placebo from the second day after CS for 20 days. Women were assessed by U/C on the 7th-10th and 20th days following CS. UTI was significantly lower in the intervention group compared with the control in the follow-ups conducted on the 7th-10th days (odds ratio = 0.22; confidence interval 95% [0.07, 0.67]; p = .006) and 20th day (odds ratio = 0.32; confidence interval 95% [0.14, 0.75]; p = .008). But the incidence of cystitis in the two groups was not statistically significant (p > .05). R. canina fruit capsules were able to reduce the incidence of UTI after CS. Thus, it is likely that administration of this medication can promote maternal health following CS.