Abstract: The wild fruit-tree forest which is distributed in the Ili Valley of the Tien-Shan Mountains in western Sinkiang, consists of Tien-shan apple (Malus sieversii), wildapricot (Armeniaca vulgaris) and wild walnut (Juglans regia), etc. It is a broad-leaved forest type with "oceanic" climate, which appears in the mountain region of desert zone. Its distribution is closely related to the complex of special ecologicalfactors, such as abundant rainfall of the locality, evident "inversion" in winter, and relief elements in which the cold air current is evaded, etc. The present forest is a valuable "relict" in the mountain region. It is a paleo-geographical phenomenon-the result in which the broad-leaved forest elements of Tertiary paleotemperate zone combine with elements of the boreal forest and meadow. It is evidently distinguished in geographical elements from the fruit-tree forest in the western Tien-shan Mountains of Middle Asia. The classification of wild fruit-tree forest in the Ill Valley is as follows: 1. Tien-shan apple and wild apricot-Tien-shan apple Formation: (1) Malus sieversii-Bromus benekenii Ass. (2) M. sieversii-Brachypodium silvaticum Ass. (3) M. sieversii-Impatiens brachycentra Ass. (4) M. sieversii+Populus tremula-Aegopodium alpestre Ass. (5) M. sieversii-Shrubs-grasses Ass. in valley. (6) M. sieversii + Armeniaca vulgaris-shrubs-grasses Ass. (7) M. sieversii+A, vulgaris-Spiraea hypericifolia-steppe grasses Ass. 2. Wild walnut Formation: (1) Juglans regia-Brachypodium silvaticum + herbs Ass. (2) J. regia-Impatiens braehycentra+Aegopodium podagraria Ass.Sparse wild apricot Formation.