Zinc supplementation reduces the severity, duration and recurrence of childhood acute diarrhoea. These beneficial effects of zinc in the treatment of diarrhoea led to the inclusion of a 10-14 days treatment regimen by the WHO/UNICEF. This study assessed the level of knowledge and use of zinc supplementation in the management of childhood diarrhoea among health care workers in public primary health facilities in Benin-City, Nigeria.Methodology:This cross-sectional study was carried out among the total population of health care providers in public primary health facilities in Benin-City. Data collection was done using a pre-tested, structured, self-administered questionnaire and data was analyzed using SPSS version 15.0.Results:A total of 168 health care workers participated in the study. Two-thirds of them were aware of zinc supplementation but specific knowledge of zinc supplementation in the management of childhood acute diarrhoea was poor. Thirty-five percent of them prescribed zinc when managing childhood diarrhoea and only 10% of these do so for every case of childhood diarrhoea. About 84.6% of them prescribed the correct dose of zinc while less than half of them prescribe it for the correct duration. All but one of them prescribed zinc in addition to ORS in line with the WHO guideline.Discussion:The study revealed a gap in the knowledge and practice of use of zinc supplementation in the management of childhood diarrhoea. It is recommended that nationwide campaigns should be embarked on to promote the use of zinc supplementation in the clinical management of childhood diarrhoea.