Foraging and bed sites are the two key habitats for the ungulate, but researches on the differences between these two habitats are little. During the summer we studied the foraging and bed sites selection for Tianshan argali(Ovis ammon karelini)in Gurenguoleng areas of Central Tianshan Mountains, Xinjiang Uygur Autonomous Region, China. According to the population and distribution of Tianshan argali in this region, we collected the ecological factors via line transect and quadrat sampling methods. During July and August in 2010, we investigated the Tianshan argali among 12 lines transects in total along 5 ditches. Line transects were allocated from the bottom to the ridge of the mountain covering all typical vegetation in this region. Due to the huge mountain and wide basin in the studied area, direct observation method can be used to determine Tianshan argali's habitat. We stood far away from the argali pack to observe their foraging or bed sites via the telescope until the targeted argali left. Then one of colleagues was responsible for guiding the other person to find the targeted area by the telescope. Some of the bed sites were confirmed by trace detection by the surrounding factors such as the fresh bed trace and fecal pellet, footprint, urine, hair, etc. The foraging and bed track of Tianshan argali was marked as the center for a 10 m×10 m quadrat when it was found during the field investigation, and the quadrat center was located with Garmin-72 GPS. In this field investigation we observed 157 foraging and 136 bed sites for Tianshan argali with 13 ecological factors: elevation, slope, slope direction, slope location, landscape type, vegetation height, vegetation coverage, hiding level, distance from road, distance to water resource, distance to livestock, distance to human settlements and number of plant species on habitat selection by Tianshan argali were thoroughly evaluated in this research. The results showed that there were no significant differences between foraging and bed sites for Tianshan argali to live among the factors in slope, hiding cover level, distance to water resource, number of plant species and vegetation coverage in summer (P > 0.05), however, the factors in altitude, distance to livestock (P < 0.01); vegetation height (P < 0.05), slope location, slope direction and landscape types (P < 0.01) were the significant factors for the Tianshan argali to live. Compared with bed sites, Tianshan argali preferred to choose the foraging sites at lower elevation, lower vegetation height, closer to roads, human settlements and livestock, habitats of a mountain alpine meadow in the semi-shaded slope and grassland in gentle slope in summer. During the long field investigation and observation we could find that there were 4 essential ecological factors play an important role in distinguishing the foraging and bed sites. We ordered them according to their contribution value index: distance to road, distance from the settlements, vegetation height and distance to livestock. Based on the mentioned ecological factors variables, the accurate rate for distinguishing the foraging and bed sites of Tianshan argali reached 90.6%. The results fully demonstrated that there was obvious habitat separation between foraging and bed sites for Tianshan argali to live during summer. Therefore, the pattern of habitat selection by Tianshan argali seemed to be strongly influenced by food, predator and disturbance.