Abstract: The micropaleoflora from the Middle Carbonate Rock Formation of Jiezha Group has been firstly studied in this paper. The abundance sporopollen and variform acritarch characterizing the formation contain 62 genera and 91 species, in which 20 gen. and 31 sp. belong to sporopollen, 42 gen and 60 sp. acritarch. Among them one is affinis, twelve conformis and five species, in addition, four species indeterminata. The sporopollen assemblage is consisted of the dominant gymnospermous pollen of 49.0% in the amount, spore 18.8% and acritarch 32.2%. In detail, the spore is mainly made from Punctatisporites, Apiculatisporis, Marattisporites, the pollen Pinaceae, Ovalipollis, Cycadopites and a few Chordasporites, Taeniaesporites, the acritarch Hystrichosphaeridium, Micrhystridiura, Favososphaeridium, besides Leiofusa Quadratimorpha, Scolecodonts, Taenitum, Lignum and so on. The geological time is middle upper Triassic. The Carbonate Rock Formation is composed of a suite of the epicontinental sedimentary strata being 1303 m thickness and formed in the stably olepositional enviroment. The region should, then, lie in the shore of Paleomediterranean sea or near the geosyncline round the Pacific. Based on the abundance gymnospermous spore fron Jiezha Group, the climate at that time should be humid torrid or subtorrid zone marine.

Key words: Upper Triassic, Middle carbonate rock formation of Jiezha Group, Micropaleoflora