Background: Spinal Muscular Atrophy (SMA) is a genetic disease affecting the central nervous system and voluntary muscle movement (skeletal muscle). This study aimed: Was to assess knowledge, attitudes and practices of mothers regarding their children with spinal muscular atrophy. Research design: A descriptive research design was used in carrying out this study. Setting: The study was conducted  at Hassan Awad Health Insurance Clinic in Banha City. Sample: Purposive sample  of 100  mothers and their children with SMA. Tools: Three tools were used. Tool 1: Consisted two parts: Part (1): An interviewing questionnaire consisted to assess  socio-demographic data of studied sample, and personal characteristics of preschool children with spinal muscular atrophy. Part (2) Mothers` knowledge regarding SMA. Tool (II) Mothers` attitude likert scale. Tool (III): Reported practices of mother regarding their children with SMA. Results: 36.0% of the children with SMA were  aged from 1< 3 years . 93.0% of studied children had motor problems of difficult  standing. 60.0 % of mothers had poor total level of knowledge regarding spinal muscular atrophy,66.0 % of them had negative attitude  and 53.0 % of studied mothers had unsatisfactory total reported practices. Conclusion: Most of studied children had motor problems of difficulty standing, There were statistically significant correlation between studied mother`s total knowledge, total attitude and total reported practices. Recommendations: Health education program should be given for mothers about SMA to enhance their knowledge, attitude and practices regarding disease.