Introduction: Fever or febrile is an increase in temperature/body temperature above 37.5ºC. The World Health Organization (WHO) put forward the number of cases of fever worldwide reaching 18-34 million. Handling fever in children is very dependent on the role of parents, especially mothers. The level of knowledge is one of the im- portant roles in managing fever in children. The purpose of this study is to determine the relationship between ma- ternal knowledge about fever and the management of fever in preschool children. Methods: This research method uses cross-sectional analysis. The respondents of this study were 109 mothers who had preschool children. Data is collected by filling out the questionnaire sheet. Results: Results showed that 68 respondents (62.4%) having poor knowledge and obtained 80 respondents (73.4%) had pretty good fever management. Based on the Chi-Square test results obtained P-value=0.003, Which Means the P-Value of p