PURPOSE: This study was done to identify the relationship between goodness-of-fit for mother-preschool child dyads and parenting stress experienced by the mother. METHODS: Study participants were 500 mothers who had children aged 3 to 5 who attended one of ten kindergartens or infant schools in M City or B City. Descriptive statistics and Pearson's correlation coefficients were calculated using the SPSS program. RESULTS: Comparison of goodness-of-fit scores for mother-preschool child dyad according to the characteristics of the participants, showed a significant difference according to child's age, gender, and birth order, mother's education and occupation, father's age and education, family income, and the chief caregiver in the family. There was a positive correlation between goodness-of-fit scores for mother-child dyad and parenting stress scores for mothers. CONCLUSION: The findings of the study indicate a need to identify differences between children's behavioral problems and parenting styles according to the degree of discord in the mother-child temperaments. It is also necessary to develop and apply nursing programs to promote harmonizing of temperaments, programs in which the characteristics of the child and the mother are considered.