The aim of this study is to examine the effect of an dialogic reading program on expressive language vocabulary and category naming skills, which are among the early literacy skills of preschool children. The research was designed in the quasi-experimental model, which is one of the quantitative research methods. The sample of the study consisted of a total of 30 children, 15 girls and 15 boys, between 64 and 72 months of age, who attended a kindergarten in Konya. Fifteen of the children were in the control group and 15 of them were in the experimental group. In addition to the existing preschool education program applied to the groups within the scope of the study, a 10-week dialogic reading program was applied to the experimental group. In the research, "Demographic Information Form" was used as the data collection tool and "Early Literacy Test (ELT)" was used as pre-test and post-test. According to the results of the research, the post-test scores of all groups' expressive language vocabulary and category naming skills increased significantly compared to the pre-test scores. However, the post-test scores of expressive language vocabulary and category naming skills of the experimental group were significantly higher than the control group. Accordingly, it was concluded that the dialogic reading program applied significantly increased the expressive language vocabulary and category naming skills, which are among the early literacy skills.