Background: Mothers of mentally retarded children have excessive burdens in caring for the children. ensuring information for mothers about safety measures in home accidents is important in reducing incidence of injuries among their mentally retarded children. Aim: This study was conducted to assess mothers' awareness regarding prevention of home accidents among their mentally retarded children in Benha City. Design: Descriptive design was utilized in carrying out this study. Sample: Convenient sample of all mothers of mentally retarded children was taken. The total sample included 140 mothers. Tools: Two tools were used for data collection. I) structured interviewing questionnaire consisted of three parts. The first part included: A: Socio- demographic characteristics of mothers. B): Personal characteristics of children. Part 2: Knowledge of mothers regarding mental retardation and home accident prevention, Part 3: Reported practices of mothers regarding first aid of home accidents. II): Mother's attitude regarding their mentally retarded children and prevention of home accident. Results: 40.8% of the studied mothers had average knowledge about mental retardation, prevention of home accidents and first aid of home accidents for their mentally retarded children. 63.6% of the studied mothers had satisfactory practice level about first aid of home accidents for their children with mental retardation. 75%of the studied mother had positive attitude about mental retardation and prevention of home accident. Conclusion: There was highly statistically significant relation between mother's total knowledge, practices and attitude about mental retardation, prevention of home accidents and first aid of home accidents for their mentally retarded children. Recommendations: Health educational programs for mothers about mental retardation, prevention of home accidents and first aid of home accidents for their mental retarded children.