Abstract: Aiming at providing theoretical basis for reasonable development and utilization, we conducted a study on the degradation pattern of forage rape in rumen of dairy cows. In this study, taking the forage rape at different growth stages, selecting holstein cows with permanent rumen fistula and using the method of rumen nylon bag, we analyzed dry matter (DM), crude protein (CP), neutral detergent fiber (NDF) of samples after they were treated at 4 h, 8 h, 12 h, 16 h, 24 h, 36 h, 48 h and 72 h, respectively, and examined the degradation pattern of forage rape in rumen of dairy cow. The results showed that DM decreased gradually as the extension of growth period, in an order of squaring stage, flowering stage and podding stage. Different growth stages greatly influenced active degradation (a), slow degradation (b) and effective degradation (ED) in degradation parameters. Value a of CP at podding stage was significantly higher than that at squaring stage or flowering stage (p<0.05), and value b of CP at squaring stage was higher than that at flowering stage or podding stage (p<0.05), respectively. Value a and value b of DM at squaring stage were significantly higher than those at podding stage (p<0.05), respectively. Value a and value b of NDF at flowering stage were significantly higher than those at podding stage (p<0.05), respectively. ED values of CP, DM, and NDF at flowering stage were significantly higher than those at podding stage (p<0.05), respectively. Degradability of forage rape in rumen of dairy cows varied with different growth stages, ED value of CP at flowering stage was higher than that at squaring stage or podding stage, and ED value of DM and NDF at podding stage was the lowest.