Abstract: An experiment has been conducted using single and drill planting methods on the wild diploid Dactylis glomerata subsp. Himalayensis and its autotetraploid in order to compare the agronomic traits of different ploidy cocksfoot. The results showed that the vegetative growth stage of wild diploid cocksfoot was longer than the autotetraploid type and that it grew rapidly at later stages. The yields of leaf and single plants in each component of autotetraploid were significantly higher than wild diploid cocksfoot at the same stage (P<0.05). With the increase of ploidy, the number of tillers, reproductive branches and 1000 seed weights increased, while the percentage of reproductive branch, spike yield, number of seeds, germination potential and germination rate decreased. Autotetraploid fertility is thus not as strong as that of the wild diploid. In terms of dry matter, autotetraploid yields from each cutting and total annual output were 20.3%-72.8% and 18.3%-41.5% respectively, which were higher than those of the wild diploid, but yields of withered grass dropped 23.9%, which was lower than that of wild diploid. Based on equilibrium analysis, autotetraploid forage balance was better than the wild diploid. In terms of nutritive value, crude protein, crude fat, ash, contents of calcium, phosphorus and hemicelluloses for both the wild diploid and its autotetraploid decreased significantly with increased maturity, while neutral detergent fiber, acid detergent fiber and acid lignin increased. With increasing ploidy levels, the percentages of nutritional components fluctuated unevenly during the growth period, with only calcium contents increasing significantly after maturity.