Objective To investigate the therapeutic effects and mechanism of Okam on asthmatic mice.Methods The mice model of asthma was established with the egg albumen sensitization, and were treated with low and large doses of Okam for four weeks.The pathological changes of lung tissues were observed.Immunohistochemistry was used to determine the contents of matrix metalloproteinases-9(MMP-9) and tissue inhibitor Metalloproteinase-1 (TIMP-1) in the lung tissues.Results Gasp and inflammation in the lung tissues were significantly relieved in the test groups than that in the model group.MMP-9,TIMP-1 and MMP- 9/TIMP-1 ratios were significantly lowered in the test group than that in the model group. Conclusion The marine drug of Okam shows therapeutic effects on mice with asthma,which may be the result of reduced contents of MMP-9 and TIMP-1 in the lung tissues and the correction of the imbalanced MMP-9/TIMP-1 ratio.Okam is likely to be a new choice for the treatment of asthma.