is a new species of microsporidia found to be affecting shrimp culture. Previous studies have shown that shrimps infected with grow slowly. In recent years, slow growth has been observed in Enterocytozoon hepatopenaei infection has been reported. To study the morphological characteristics of in Jiangsu Province and interpret the differences in context of the reports from other studies conducted abroad, this study used Penaeus vannamei cultured in Jiangsu Province as the research material. Preliminary isolation and purification of through sucrose density gradient centrifugation was performed. A method of diagnosing using Fluorescent Brightener 28 staining was established and the spore morphology was observed under a microscope. The results showed that the spores of were mainly distributed along the sucrose gradient of 35%-40%, and their buoyant density was 1.15g/mL-1.17g/mL. The spores were elliptical or round, bright blue, and small, but countable under the fluorescence microscope. The spores were approximately 1.7 μm×0.9 μm. The spore surface is covered with small folds and there is a large amount of white nodules present on their outer wall, which may be wall protein; the cell wall is composed of a relatively thin, electron-transparent inner wall and an electron dense spore wall. The spores have a nucleus, and 4-6 coils of the pole filament. The morphological structure of in Jiangsu was consistent with the reports abroad. The methods of isolation, purification, and fluorescent staining developed, as well as the morphological data of obtained in this study provide reference for diagnosis and research.