The contamination levels of benzotriazole ultraviolet absorbers (BUVAs) were determined in breast milk samples from 36 Japanese mothers. BUVAs were detected in all samples in the ranges of 11.0-803 ng/g lipid weight. Especially, 2-(2H-benzotriazol-2-yl)-4,6-bis(1,1-dimethylethyl) phenol (UV-320) accounted for 36% of the total. The BUVAs levels were comparable to some previous reports. The total BUVAs levels in this study were higher than those of Vietnam and Korea. A comparison of primiparas and multiparas showed that the mean total BUVAs level in multiparas was 2.1 times higher than that in primiparas. In particular, UV-320 levels were significantly higher in multiparas than in primiparas (p<0.05). Subsequently, the estimated daily intake of infants was calculated to be 76.5-4,410 ng/kg/day. Further studies are needed to help develop regulations for these chemicals in our living environment and prevent harmful exposure.