Abstract: In order to determine the optimum sowing date of Qiancao NO.4 cocksfoot under the climatic condition of Guizhou, the effect of 5 different fall sowing dates on plant height, fresh yield, ratio of dry weight to fresh weight and the leaf stem ratio was investigated. The results showed that the cutting frequency was increased by early sowing as possible, the fresh yield was increased and the ratio of dry weight to fresh weight and the leaf stem ratio were both higher. The optimum sowing date of Qiancao NO.4 cocksfoot was in the middle of September and the fresh yield exceeded 75 000 kg/hm2.