Three Chinese Holstein cows with permanent ruminal cannulas were selected to evaluate the nutritive value and to investigate the rumen degradation rate and degradation characteristics of the first cut(1st cut) premium timothy hay, second cut(2nd cut) timothy hay and oat hay for dairy cows. The results showed that the mass fractions of the crude protein(CP) and ether extract in 1st cut timothy hay and 2nd cut timothy hay were significantly higher than those in oat hay, while the water soluble carbohydrate and relative feed value were significantly lower than those in oat hay. There was no significant difference in nutritive values content between 1st cut timothy hay and 2nd cut timothy hay. In the rumen, the effective dry matter degradation rates of oat grass, 2nd cut timothy hay and 1st cut timothy hay were 48.22%, 41.76% and 36.54% respectively, and the differences among them were statistically significant. There was no significant difference in the CP effective degradability between 2nd cut timothy hay(53.09%) and oat hay(53.20%), but both of them were significantly higher than that in 1st cut timothy hay(36.67%). There was no significant difference in the neutral detergent fiber effective degradability between 2nd cut timothy hay(36.61%) and oat hay(35.10%), but both of them were significantly higher than that in 1st cut timothy hay(28.62%). Together, it can be seen that 2nd cut timothy hay has the potential as a conventional roughage resource for dairy cows and can be used to replace oat hay.