Objective To investigate the optimal dose of mifepristone and lithospermum combination regimen on medical abortion in early pregnancy rats without increasing side effects. Study Design Sixty sexually mature female Sprague Dawley (SD) rats with early pregnancy were randomly allocated into 10 groups, including a control group (treated with 0.5% CMC-Na) and nine experiments (treated with 1 mg/kg mifepristone, and 90, 180, 270, and 540 mg/kg lithospermum, and 90/180/270/540 mg/kg lithospermum +1 mg/kg mifepristone, respectively). The hormone levels, factors associated with endometrial bleeding, oxidative stress, and apoptotic proteins in the endometrium, were then investigated. Results The results demonstrated that 540 mg/kg lithospermum plus 1 mg/kg mifepristone treatment significantly improved the abortion rate when compared with the control group. Compared with the 1 mg/kg mifepristone, 540 mg/kg lithospermum plus 1 mg/kg mifepristone treatment did not induce significant increase in factors associated with abnormal endometrial bleeding, such as matrix metalloproteinase-9 (MMP9). However, mifepristone and lithospermum combination regimen promoted the expression level of malondialdehyde (MDA), activated caspase 3, caspase 9 and Bax, meanwhile, reduced the expression of superoxide dismutase (SOD) and Bcl-2. Conclusion These findings provided strong evidence that mifepristone and lithospermum combination regimen can obtain satisfactory abortion effect without increasing the expression level of bleeding-related factors.