The purpose of this research was to compare the perfectionism, coping styles, and failure tolerance of mothers of normal students and students with developmental disabilities in the elementary school of Darab city in Iran.

Research Methodology: The current research was fundamental in terms of its purpose, and in terms of how to obtain the required data, it was classified as a descriptive research and a comparative causal research. The statistical population in this research was 99 mothers of students with intellectual and developmental disabilities in the academic year of 1402-1401. According to the use of matching method and in a targeted way, based on the age and education of mothers, 40 people from each group were selected as the sample size. The data collection tool in this research was Harrington's Failure Tolerance Questionnaire (2005), Hill's Short Form Perfectionism Scale (2004), and Billings and Moss' Coping Style Questionnaire (1984).

Findings: After analyzing the data with the help of SPSS software, the results showed that according to the significance level and the low mean difference (3.82) in the t-test results, it can be concluded that there is a difference between the perfectionism of mothers of normal students and knowledge There was no significant difference among students with developmental disabilities. And there is a significant difference between the coping style of physical control of mothers of normal students and students with developmental intellectual disability.

Conclusion: Perfectionism and coping styles and tolerance of failure in mothers of students with intellectual and developmental disabilities are of special importance, and tolerance of failure in this category of mothers was significantly different from other mothers.