The purpose of this study was to analyze the differences of mothers' child-rearing stress level and their language patterns depending on fathers' role plays and couple's dialogues. For this study, 720 pre-school children aged between 5 and 7 were sampled from kindergartens and children's houses: 'T' children's house at Seongdong-gu, Seoul, 'S' public children's house at Jungwon-gu, Seongnam-si, 'D' children's house, 'Y' kindergarten, 'J' kindergarten and 'D' kindergarten at Sangrok-gu, Ansan-si, and 'W' municipal children's house. Then, a questionnaire was distributed to each of their parents, and 453 copies of questionnaire were returned. As a result of reviewing them, 76 copies were found poor due to no response, incomplete answer or omission of fathers' role play columns, and thus, 377 copies were used for analysis finally. The collected data were processed using the SPSS program for Cronbach's α coefficients about the reliability of the scales, and ANOVA(one-way Analysis of Variance). According to this study, the mothers with their husbands playing fathers' roles continuously feel less stressful for their child-rearing, and therefore, they can interact with their pre-school children more positively. Furthermore, a healthy and effective dialogue between wife and husband will help to lower the level of mothers' child-rearing stress. And such positive dialogue will encourage mothers to use the commanding languages less for their pre-school children, and thereby, will have a positive effect on children's language development as well as the evolvement of their egos during the important period (5~7 years old) of their growth.