In the present study, the effects of drought stress on seedling growth and physiology of three wild forages (Leymus secalinus, Elymus nutans, and E. sibiricus) in Tibet were investigated using pot experiments in a climate incubator. The drought resistance of the three forages was evaluated. One of the objectives of this study was to contribute to the breeding of drought-tolerant forage germplasm. The results showed that with increased drought stress, the relative water content of the soil decreased rapidly initially, and then slowly, and varied among different species. The average growth rate, plant water content, and leaf chlorophyll content decreased, but the proline content, MDA content, and SOD activity of the plants increased, as drought stress was prolonged. Moreover, the soluble sugar content of the plants decreased initially, and then increased as drought stress was prolonged. Briefly, the soluble sugar minimum values of all the plants occurred at day 5 after drought stress treatment, but soluble sugar content of E. sibiricus was still lower than that of the control after 20 days of drought stress treatment. The soluble protein content of E. nutans increased as drought stress was prolonged, but the soluble protein content of L. secalinus and E. sibiricus decreased initially and then increased with the duration of drought stress. The soluble protein contents of E. sibiricus were the lowest during the first 10 days of drought stress, whereas the soluble protein contents of L. secalinus were at the minimum level during the first 5 days of drought stress. By using the eight indicators for the three wild forage seedlings under drought stress, we performed a comprehensive evaluation of drought tolerance of the three wild forage seedlings with subordinate function and indicated the order of drought tolerance as L. secalinus > E. nutans > E. sibiricus. Therefore, the drought resistance of L. secalinus was the strongest, and it was suitable for planting in the arid regions of Tibet, but L. secalinus and E. nutans with lower sexual reproduction rates were suitable grass species for ecological restoration in arid and semi-arid areas in Tibet.