Background: Diarrhea is one of the most common causes of death in children, and there is also a direct relationship between low level of zinc and diarrhea. The purpose of this study was to evaluate the effect of zinc sulfate on acute diarrhea in children, in terms of the socioeconomic status of parents in Isfahan City, Iran. Methods: In this clinical trial study, 82 children with acute diarrhea, referred to clinics affiliated to educational centers in Isfahan, entered the study according to the criteria for entering socioeconomic level (low or high). The intervention group (38 cases) received zinc sulfate according to the age group, and the placebo group was under treatment with placebo same as the other group. The data of this study were compared between the two groups. Findings: The mean recovery time in the intervention group was significantly lower than placebo group (P < 0. 050). Moreover, in the follow up of 5 and 14 days, the incidence of diarrhea, outpatient visits, and hospitalization in the intervention group was significantly lower than placebo group (P < 0. 050). In follow up of 1 and 3 months, the incidence of diarrhea and hospitalization was significantly lower in the intervention group compared to placebo group, too (P < 0. 050). Conclusion: The use of zinc sulfate in patients with different socioeconomic levels is a highly effective, safe, and non-adverse drug supplement to reduce the incidence, severity, recovery period, outpatient visits, and hospitalization due to diarrhea.