This paper adopts a linear regression model to study the relationship between picture book color and purchase intention. The research object is selected, the research data are obtained by distributing questionnaires, the correlation coefficient formula of the linear regression model is used to get the correlation of the research independent variables, and then the least squares method is used to conduct regression analysis of picture book color preference and purchase intention. The research data show that the R² of model 1 (control variable) is 0.015. The R² of model 2 (independent variable) is 0.625, which increases the degree of explanation by 61.00% compared with model 1. The regression coefficients of the independent variables are 0.214, 0.122, and 0.126, respectively. All of them reach a significant level, which indicates that there is a significant positive effect of the color preference of picture books of Chinese and Korean children between the ages of 3-7 on the willingness to purchase. The color preference of Chinese and Korean children’s picture books aged 3-7 has a significant positive effect on purchase intention, as indicated by this. The cross-border children’s book market can benefit from this study as a good sales strategy and suggestion to better promote children’s picture books.