Abstract Introduction: Worm infestation affect the child growth and development and it leads to major complication if the children are not treated in the earlier stage. The mother plays a major role in child care as is the prime care giver. Objective: The objective of the study was to assess the knowledge on worm infestations among mothers with underfive children in Maraimalai nagar. Methodology: The research approach selected for the present study was Quantitative approach and descriptive research design. The study was conducted in Maraimalainagar, Kancheepuram District. The study was conducted among 50 mothers with under five children. Non probability purposive sampling technique was adopted for the study. The data was collected using structured questionnaire which consists of 20 questions. Results: 50 mothers, 18 (36%) mothers have in adequate knowledge; 20 (40%) mothers have moderately adequate knowledge and 12 (24%) mothers have adequate knowledge. Conclusion: Hence the knowledge of the mothers can be enhanced through mass awareness program on prevention of worm infestation which in turn promotes the health of the under five children.