OBJECTIVE： To investigate the effects of 4 polar parts extracts from Li medicine Alpinia oxyphylla fruit on model mice with experimental colitis， and screen the effective parts of A. oxyphylla fruit in the treatment of colitis. METHODS： After 70％ ethanol extract dispersed by water， petroleum ether， trichloromethane， ethyl acetate and n-butanol were used in turn to obtain extractions in related parts. 42 mice were randomly divided into modeling group （36 mice） and blank group （6 mice）. Mice in modeling group were taken 2，4，6-nitrobenzne sulfonic acid method to replicate the experiment colitis. After modeling， model mice were randomly divided into model group， positive group （Sulfasalazine enteric coated tablets， 52 g/kg）， petroleum ether， trichloromethane， ethyl acetate， n-butanol extract from A. oxyphylla fruit groups （10 g/kg， calculated by crude drug）， 6 in each group， intragastrically administrated once a day， for 9 d， 0.2 mL/10 g； mice in blank group and model group were intragastrically given normal saline. After administration， body mass of mice was determined， disease activity index （DAI） was scored and colonic myeloperoxidase （MPO）， superoxide dismutase （SOD）， malondialdehyde （MDA） activities in colon tissue were detected， and the colon pathological changes were observed and scored. RESULTS： Compared with blank group， decrease percentage of body mass， DAI score， MPO and MDA activities in colon tissue in model group were increased （P＜0.05 or P＜0.01）； colon tissue was pathologically changed. Compared with model group， body mass was increased， DAI score， MPO activity and pathological score in each administration groups were decreased； SOD activities in positive group， n-butanol extract from A. oxyphylla fruit group and ethyl acetate extract from A. oxyphylla fruit group were significantly increased， MDA activities in positive group and ethyl acetate extract from A. oxyphylla fruit group were significantly decreased， with statistical significances （P＜0.05 or P＜0.01）. CONCLUSIONS： The 4 polar parts extracs from A. oxyphylla fruit have certain improvement effects on model mice with experimental colitis， in which ethyl acetate and n-butanol parts are preferred.