This study aimed to examine how discussion activities that use environmental picture books affect young children’s environmental sensitivity and environmental conservation knowledge. A total of 28 five-year-old children (14 in the experimental group and 14 in the comparison group) attending kindergarten A in K City, Gyeonggi Province, participated in an experimental intervention consisting of discussion activities with environmental picture books conducted three times per week for eight weeks. Data underwent analysis using SPSS 29.0, with means and standard deviations calculated, and analysis of covariance conducted. Findings showed that, first, discussion activities with environmental picture books produced statistically significant differences in overall environmental sensitivity between the experimental and comparison groups. Significant differ ences between groups were also observed in environmental sensitivity subdomains: sensitivity, aesthetic and emotional stability, and sympathy and compassion. Second, statistically significant group differences were also found in overall environmental conservation knowledge and its sub domains: water conservation, air conservation, soil conservation, and recycling. These results suggest a positive effect of discussion activities based on environmental picture books on young children’s environmental sensitivity and environmental conservation knowledge.