OBJECTIVE：To evaluate the inherent quality differences of different batches of Compound norethisterone tablet from different domestic enterprises by researching its in vitro dissolution， to provide reference for improving relevant standards in pharmacopoeia and optimizing production processes in drug manufacturers. METHODS：Orthogonal test was adopted to screen its dissolving conditions， small glass method was finally confirmed by detecting rotating speed， sampling time and dissolution medium， sampling determination was conducted with the dissolution medium of 0.5％ sodium dodecyl sulfonate and rotating speed of 50 r/min and 45 min. And HPLC was adopted to simultaneously determine the in vitro dissolution of norethindrone and ethinyl estradiol， then AV value method was adopted to detect the similarity of dissolution profiles of 8 batches of products from 2 domestic enterprises. RESULTS：The dissolution profiles and similarity of AV value method showed the cumulative dissolution of 8 batches of Compound norethisterone tablet from 2 domestic enterprises had no significant difference at different time points， overall similarity was relatively high； but the ethinyl estradiol had certain difference， overall similarity was relatively low. CONCLUSIONS： The difference of dissolution profiles of Compound norethisterone tablet may has effect on the drug efficacy， the production process and quality in domestic enterprises should be managed strictly. Meanwhile， the current method of dissolution is weak to distinguish from the quality， which needs to be improved urgently.