This study was conducted to determine the annual variations in crude protein, crude cellulose, P, K, Ca and Mg contents, and the ratio of K/(Ca+Mg) of crested wheatgrass, subalpine brome, sheep fescue, junegrass, needlegrass, hybrid alfalfa and cat thyme in Erzurum rangelands, during the 1994 growing season. Crude protein, P, Mg and K contents steadily decreased toward to end of the growth stage although cellulose content increased. Ca content increased until blooming stage in all plants. Plant leaves had richer nutrient contents than the stems in all growing periods. The K/(Ca+Mg) ratio was high at the beginning of the vegetative stage especially in grasses, but quickly decreased after stem elongation.