Abstract：Objective：To observe the effect of icariin on the expression of type Ⅱ collagen and proteoglycan in rabbits' degenerative lumbar disc tissues，and to explore the mechanism of icariin in the prevention and treatment of lumbar disc degeneration. Methods：A total of 30 rabbits were divided into the experiment group，the model group and the blank group according to the random number table method，10 rabbits in each group. The experiment group and the model group was adopted a method of puncture and aspiration of the nucleus pulposus to replicate models with lumbar disc degeneration. Four weeks after the operation，the experiment group received icariin at a dose of 3 mg/(kg·d)，and the model group and the blank group received the same amount of normal saline by gavage；all groups were intervened for four weeks. Four weeks and eight weeks after the operation，five rabbits in every group were selected and sacrificed by air embolization to obtain their lumbar discs. The histopathological changes were observed from HE staining；the expression levels of type Ⅱ collagen was determined by immunohistochemistry，and the content of proteoglycan was determined by phloroglucinol spectrophotometry. Results：Four weeks after the operation，there was a high content of matrix in the nucleus pulposus of the blank group with uniform density and deep staining，contained with a lot of nucleus pulposus cells whose nucleus was hyperchromatic and cytoplasm lightly stained. In the experiment group and the model group， the matrix in the nucleus pulposus and nucleus pulposus cells partially disappeared and were replaced by hyperchromatic fibrous tissue and fusiform fibroblasts. Eight weeks