Summary The objectives of this research is to compare about parenting stress that faced by the Malaysian mothers of children that have mental retarded and a contorl goup, and to determine factors associated with stress. The methods used in this research are Parenting Stress Index (PSI), Parent Domain Stress (PDS) and Child-domain (CDS). CDS measures the characteristics of a child while PDS measures the personality of parents including the environment. PSI is about the past experience that could lead to stress. The children’s cognitive functions were assessed through Weschler Intelligence Scale for Children (WISC-III) or Weschler Intelligence Scale for Pre-Schoolers (WIPPSI). Parents also need to take the Child Behaviour Checklist (CBCL) as for their perception on children's behaviours. The data indicated that nine (12%) out of 75 had down syndrome, 32 (42.7%) had retardation attributed to a perinatal insult (prematurity, perinatal asphyxia and interine infection and six (8%) to brain injury in early childhood. While the remaining 28 (37.3%) was not known. In result, others of children with mental retardation scored significantly higher than control subjects in both the child-related domain (difference between means 26.1, 95% confidence interval 19.6–32.5) and parent-related domain (difference between means 15.0, 95% confidence interval 7.9–22.1) of the PSI. The total child behavior scores from the CBCL (P < 0.01), IQ scores (P < 0.01) and sibship size (P < 0.01) were associated with child-related domain scores. For the parent-related domain, CBCL (P < 0.01) and IQ scores (P = 0.01) remained important factors but Chinese ethnicity (P < 0.01) and maternal unemployment (P < 0.01) were also significant predictors of stress. To conclude, mothers' emotional distress has been linked to the development of psychiatric illnesses in their children.The findings of this study suggest that interventions to reduce stress in our study population should include appropriate psychosocial support and counseling for families, particularly Chinese and unemployed mothers, with a focus on positively changing parental perception and handling of child behavior. Full article: https://onlinelibrary.wiley.com/doi/abs/10.1046/j.1440-1754.1999.00383.x Ong, L.C, Chandra, V. & Peng, R. (1999). Stress experienced by mothers of Malaysian children with mental retardation. Journal of Pediatrics and Child Health, (35)4, 358-362. https://onlinelibrary.wiley.com/doi/abs/10.1046/j.1440-1754.1999.00383.x