Abstract: Objective To establish the model of chondrocyte cultured in vitro,and to study the biological differences between fibrocartilage and hyaline cartilage. Methods Condylar cartilage and epiphysis cartilage were aseptically dissected from 4weekold New Zealand white rabbit.Cells were obtained by enzyme digestion and cultured in vitro until the 10th passage.The fibrocartilage cells and hyaline cartilage cells were observed and analyzed by inverted microscope,alcian blue staining and immunohistochemical staining.Cells growth curves were made with the method of cell counting.Quantitative realtime PCR and western blot technique were used to detect and analyze the expression of collagen Ⅰ,collagen Ⅱ,collagen Ⅹ,SOX9 and Aggrecan.Oneway ANOVA with SPSS13.0 software package was performed. Results With the increase of subcultures,both fibrocartilage cells and hyaline cartilage cells changed morphologically into fibroblastlike cells,especially after P2.Detection of gene and protein level has demonstrated that the dedifferentiation of chondrocytes was obvious after P2 generation.The chondrocytes staining was positive in the slides of cells.Quantitative realtime PCR and western blot both showed that the expressions of colagenⅠ,collagen Ⅱ,collagen Ⅹ,SOX9 and Aggrecan in fibrocartilage were significantly different from those in hyaline cartilage.The expression of colagenⅠin fibrocartilage was higher than that in hyaline cartilage while other expressions were lower. Conclusions It is a simple and effective way to culture chondrocytes in vitro in this study.Our research confirms that the tendency of dedifferentiation would occur in both fibrocartilage cells and hyaline cartilage cells.There are essential differences between fibrocartilage and hyaline cartilage in biological characteristics.