Abstract: Forty-six species of fossil spores and pollen referred to 30 genera extracted from the crude oil samples collected from the Kashi Depression of the Tarim Basin in Xinjiang were recorded . Based on the investigations of the palynomorphs in crude oil. the petroleum source of the petroliferous region was traced and the petroleum migration mechanism is discussed. The fossil spores and pollen found from crude oil of the Neogene reservoir of the Kelatuo Oilfield of the Kashi Depression comprised mainly Deltoidospora lineata, Cyathidites australis, C. minor, Gleicheniidites rousei, Dictyophyllidites harrisii, Cibothtmspora paradoxa, Todisporites major, Granulatisporites minor, Leptolepidites major, Klukisporites variegatus, Murospora jurassica, M. minor, Paleoconiferus asaccatus, Vi!reisporites jurassicus, V. shouldicei, V. jansonii, Alisporites thomasii, A. lowoodensis, Podocarpidites florinii, P. langii, P. multicinus, P. multesimus. Quadraeculina limbata, Protopinus scanicus. Protopicea exiliolides, Piceites expositus. P. latens, Pinuspollenites labdacus. Piceaepollenites alatus, Cedripites minor, Chasmatosporites major, C. elegans, C. canadensis, Cycadopites nitidus, C. typicus, Ephedripites tertiarius, CerebropoUenites carlylensis, Classopollis classoides, C. annulatus, Caryapollenites simplex, Chenopodipollis multiplex, Artemisiaepollenes sellularis, etc. According to the characteristics of the petroleum sporo-pollen assemblage, the Lower Jurassic Kangsu Formation and the Middle Jurassic Yangye and Taerga Formations should be the petroleum source rock series of the Kashi Depression. Judging from the palynomorphs of the source rocks found in crude oil. It might be concluded that the fossil spores and pollen together with oil beads must have been expelled from the source rocks along microfissure avenuses during the primary migration along fissures, joints faults, and unconformity planes during the secondary migration.

Key words: Spore and pollen, Petroleum source, Petroleum migration: Jurassic