The purpose of this study is to examine the effect of book reading education for mothers of multicultural families on their infants' language development. 22 mothers of multicultural families participated in this experiment. 15 among mothers participated in education of book reading. 7 mothers of multicultural families didn't participated in our education of book reading. The subject group lived in Korea for five years 8 months. The control group lived in Korea for six years 2 months. The book reading interaction of 22 mother-infant(4 year 3month～4year 4moth olds) pairs was video-recorded. Mother-infant behaviors was measured during book reading. The mothers' type of questions and their infants' frequency of spontaneous speech was measured. In mothers of multicultural families who participated in education of book reading, there were significantly positive correlations between book reading education and waiting, commenting, questioning, nonverbal responses, encouraging and labelling. But In control group, there were simple book reading, ignoring, commenting, interest-evoking and infant behavioral modification. The frequency of the question and of open-ended question were significantly more in mothers who participated in education of book reading than mothers who didn't. The frequency of spontaneous, responsive, and total utterance were significantly more in infants with mothers who participated in education of book reading. These results demonstrate that it is important for mothers in multicultural families to learn the method of effective book reading for their infants' language development.