This paper reports a kind of anatomically preserved bilaterally symmetrical marattialean synangia from the coal balls in coal seam No. 7 in Taiyuan Formation (early Early Permian) of Xishan coal field, Taiyuan, Shanxi. These synangia are the earliest in the geological time in the bilaterally symmetrical marattialean synangium ever found in the Cathaysian Flora so far. Compared with other anatomically preserved bilaterally symmetrical marattialean synangia in the world, these synangia are assigned into Eoangiopteris Mamay and a new species, E.shanxiensis sp. nov., is proposed. The diagnostic characters of the new species are as follows: The fertile pinnule is at least 2.6 mm wide but its length is unknown because of poor preservation. The midrib of the pinnule possesses a “C” shaped vascular bundle. The fertile pinnule is down-turned at its margin and the arrangement of the synagia is not affected. Synangia are 0.75~1.1 mm in height and 0.35~0.55 mm in diameter and consist of 8~12 sporangia arranged in two rows along the lateral veins. Synangia bear a short and conspicuous reptacle consisting of parenchyma enclosing vascular tissue. Sporangia are elongate with a conspicuous and solid tip and are 150~250 mm in diameter and 550~850 mm in height. The out-facing sporangial walls are 2~3 cells thick in the middle and lower part and 3~4 cells thick in the upper part of the sporangia and the cells are nearly isodiametric with the slightly thickening walls. The inner-facing and lateral sporangial walls are only one cell thick and the cells are tangentially elongate in the middle and lower part and radially elongate at the upper part of the sporangia with the thinner walls. Spores are numerous (probably more than one thousand in quantity), spherical, trilete and small (8~13 mm in diameter) with the smooth exine and slightly granular ornamented perine. The systematic position of the new species is discussed and it belongs to Psaroniaceae with great possibility. The paleophytogeographic significance of the new species is considered based on the distribution of the bilaterally symmetrical marattialean synangia in the Euramerican and Cathaysian floras. The environmental condition of the new species is discussed based on the constitution of fossil plants in the coal balls and the ecological anatomic structures of some plants.