Based on the investigation of 48 species of fossil spores and pollen belonging to 33 genera found in the Middle Jurassic Taerga Formation in the Wuqia area of Xinjiang Autonomous Region， the late Middle Jurassic palynoflora in the area has been established. The palynoflora of the Taerga Formation is characterized by the dominance of Coniferales including Cheirolepidiaceae， Pinaceae，Podocarpaceae，Araucariaceae and Taxodiaceae， and the subdominance of Filicales including Cyatheaceae， Dicksoniaceae， Osmundaceae， Lygodiaceae and Dipteridaceae. In accordance with the character of the palynoflora， the late Middle Jurassic paleoecological，paleoclimatic and paleogeographic character as well as the relationship between paleoenvironment and petroleum source rocks in the area have been discussed. The results of this study indicate that the late Middle Jurassic paleoclimate in Wuqia area should belong to the semihumid to semiarid type of subtropic zone. It is suggested that the climate should be relatively humid during the Bathonian Stage. By the Callovian Stage， the climate began to dry out and had a tendency towards drought. The biodiversity of the palynoflora and the zonation of the plant geographic distribution reflect that the late Middle Jurassic palaeogeography in the area should possess various landscapes，including multipeaked mountains， rivers， lakes， marshes， deltas，etc. The palynological data show that the lacustrine and marsh deposits under the hot or warm and relatively humid climate conditions in the Bathonian Stage in Wuqia area might be favorable source rocks for the formation of oil and gas.