AIM: To investigate the clinical study on the effect of salvia ligustrazine injection on pregnant women with ICP in late pregnancy. METHODS: Two hundred and eighty-nine mild cases and one hundred and fifty-seven severe cases of pregnant women with ICP selected by ICP diagnosis and treatment guidelines (2015) were randomly divided into treatment group and control group. Mild control group received ursodeoxycholic acid 250 mg, oral, 3 times a day; severe control group received ursodeoxycholic acid 250 mg, oral, 3 times a day and S-adenosy-L-methionine 1.0 g, ivgtt, once a day. The treatment group was added with 5% glucose injection 500 mL+salvia ligustrazine injection 10 mL, ivgtt, once a day on the basis of the control group. Seven days counts for a course of treatment, the serum total bile acids (TBA), alanine aminotransferase (ALT), aspartate aminotransferase (AST), human chorionic gonadotropin (hCG), S/D ratio of umbilical artery blood flow and pruritus scores were measured before and after treatment. RESULTS: After treatment, the levels of TBA, ALT, AST, hCG, S/D ratio and pruritus score in mild ICP were lower than those before treatment, there was statistically significant difference before and after treatment in both groups (P<0.05),and there was no significant difference between the treatment group and the control group (P>0.05). After treatment, the levels of TBA, ALT, AST, hCG, S/D ratio and pruritus score in severe ICP were lower than those before treatment, there was statistically significant difference before and after treatment in both groups (P<0.05), and there were significant differences between the treatment group and the control group (P<0.05); there was a positive correlation between serum hCG and S/D ratio (in mild group r=0.498,0.479, P<0.01;in severe group r=0.491,0.475, P<0.01). CONCLUSION: Salvia miltiorrhiza injection can reduce the biochemical indexes, S/D ratio and hCG level of severe ICP pregnant women, and improve the symptoms of pruritus, but no obvious treatment effect on mild ICP pregnant women was observed.