Abstract: The Keriya River is the second largest river stretching into Taklinakan Desert for 420 km, except Hetian River. Along with the trend of gradual decrease of discharge of the river downwards to lower reach, the geomorp-hological landscape along the river changes obviously from section to section. The Keriya River, after flowing out of the maintain pass, forms alluvial fan. its upper part is composed of gravel alluvium, middle part a farming oasis composed of silt and sandy loam, lower part composed of saline soils At lower course of Yeying, these two tributaries form two dry deltas respectively. On the eastern dry delta, river system is distributed in fan-shaped, the riverbed density reaches 4-8 km/km², there are intermittent rivers reached here and desert woodlands-Populus diversifolia and Tamarix spp.distributed along the river rings, covering an area of 210 km², where a few residential area distributed on it. As islands of sea, the complex sand dune chains were dissected by running water, forming isolated distribution of complex sand dunes on it. On the western dry delta, the dry riverbed on fan-shaped river system is intermittently distributed. It is completely a less-populated area with huge megadunes, longitudinal dune chains, eroded shrub sand mounds and withered Populus euphratica occurred on the riverbed. There are some ruins of ancient towns distributed discontinously on the river bank of the western tributary, which reflects that once there existed human activities in the historical period. Wind is the leading agent of the change of aeolian landforrn along the Keriya River course and the running water causes a great impact on regional variance of aeolian landform in extremely arid desert zone. The flooded riverring at the upper section of the lower reach of the Keriya River(from Daheyaa to Hetian) was affected by intermittent water and vegetated with reeds without development of mobile dunes. The first terrace of the upper flooded riverbed, is generally 1.5-3m high from riverbed and interspersed with Tamarix shrub, Populus euphratica woodlands. On sparsely wooded terraces, barchans, sanddune chains and shrub vegetated sand mounds have been formed by blown sands in situ. The second terrace, 8-9 m above the riverbed, is mainly tamarix vegetated area. Under the influence of the surrounding shifting sand encroachment and the reactivation of the fixed sand dunes after the vegetation being destroyed, the alternated landscape of barchans, sand dune chains and shurb vegetated sand mounds were formed. The third terrace, is completely covered with barchans, sand dune chains. The lower reach of the Keriya River,(northern section of Daheyan) refers to the dry delta on the fan-shaped plain, the water system of the Keriya River is scatterd in a fan-shaped way, forming a natural oasis with better water condition, the most remarkable characteristics of the aeolian landform on the dry delta lie in the complex sand dunes were intercepted into isolated ones by Populus euphratica trees and tamarix spp. shrubs. The barchans and embryonic forms have developed on the high dried riverbed under wind force, and developing in a certain period(formed since 1960). The lower section of lower reach of the Keriya River(northern end of dry delta) was completely covered with moving sand dunes. The traces of the past river can be reflected by the tortuous whithered Populus euphratica and tamarix spp. vegetated sand mounds, the furthest one reaches to the ancient Tarim River. In the lower reach of the Keriya River, the key factor leading to intensify the desertification process, is misuse of water at the middle reach and impacts of human activities which caused the environmental degradation, the encroachment of mobile dune is not considered as the main factor. Therefore, in consideration of the problem of preventing the environment of natural oases at lower reaches from being degraded, rationally distributing reasonable amount of water to the dry delta to keep equilibrium of ecobalance the river course is the best way to control desertification process.The natural oases at the lower reach of the Keriya River should be preserved as one of national park in desert. In addition, effort should be made(mainly in completing the existing protection system in the interior of oases, protecting the existing natural vegetation on the periphery of oasis) to maintain the stability and development of oases.