This study aims to identify the expression of p53 on placenta and pregnant mice's foetus growth exposed by carbon black. The experimental units divided into five groups: negative control is pregnant mice without carbon black exposure and without Chlorogenic Acid therapy; positive control is pregnant mice exposed to carbon black without Chlorogenic Acid therapy; treatment 1, 2 and 3 were pregnant mice exposed to carbon black with Chlorogenic Acid therapy at 4.5 mg/kg body weight, 9 mg/kg body weight and 13.5 mg/kg body weight. The stages of the study began by mating female mice before exposing them to 1064 mg/m 3 carbon black for 8 hours, then administered with Chlorogenic Acid therapy. The detection of p53 expression was done with immunohistochemical staining and foetus growth with Alizarin red method observation. The results of the study show that chlorogenic acid administration has significant effects (p≤0.05) to the decrease in p53 placental expression compared to the positive control, hence the negative control (7.36 cm± 0.65 a), the positive control (32.00cm ± 0.21157 a), treatment 1 (25.00 cm± 0.3338 b), treatment 2 (16.93 cm± 0.39036 c) and treatment 3 (11.43cm ± 0.1397 d). There were significant differences in the length and weight of foetuses born between treatment groups (p≤0.05), hence the length of the foetus in the negative control (1.50 cm± 0.04 d), positive control (0.82 cm± 0.02a), treatment 1 (0.86 cm± 0.01 a), treatment 2 (1.01 cm± 0.98 b), and treatment 3 (1.44cm ± 0.03 cd). The foetal weight in the negative control is 4,082 g ± 0,131 c , in the positive control is 2,022 g ± 0,107 a , in the treatment 1 is 1,844 g ± 0,406 a , in the treatment 2 is 3,218 g ± 0,388 b , in the treatment 3 is 4,009 g ± 0.879 c. This study concludesthatthe administration of chlorogenic acid in pregnant mice exposed to carbon black can reduce the p53 expression on the placenta and also improve the placenta'slong and heavy performance.