Abstract: The Anchang syncline is a complex tectonic area for shale gas exploration in South China, located in the northern part of Guizhou Province. The shale of the Upper Ordovician Wufeng-Lower Silurian Longmaxi formations in the well Anye 1 in Zunyi area of Guizhou Province was studied using argon ion polishing, scanning electron microscopy, N₂ low-temperature low-pressure adsorption experiments and organic geochemical, rock and mineral analysis and other supporting experiments to portray microscopic pore type, structure and their controls on the gas content of marine shale reservoirs. There are many kinds of micro and nano pores in the Wufeng-Longmaxi shale, and organic pores and micro cracks are the most abundant. The shale hosts mainly nano pores, and the micro pores are mostly filled with calcite. Organic pores are the main pore types of the Longmaxi shale, and micro cracks are the main pore types of the Wufeng shale. There are two kinds of N₂ adsorption-desorption isotherms:type IV-H₄ hysteresis loop and type V-H₃ hysteresis loop, which are slit pores with a flat structure. The BET specific surface area is between 7.87 and 14.83 m²/g, the total pore volume of BJH is between 0.002 6 and 0.005 2 cm³/g, mainly mesopores, and the average pore diameter is concentrated at 2-5 nm. In the longitudinal direction, microscopic pores have a significant control on the gas content of the Wufeng-Longmaxi shale in the well Anye 1. The shale adsorption amount is positively correlated with the TOC content, and the other parameters have no obvious correspondence with the gas content. Compared with the Wufeng-Longmaxi shale in the Jiaoshiba area, those in the well Anye 1 have different thickness, porosity, permeability and pore throat diameter, which are the main controls for gas content. Through the single well analysis of well Anye 1, it is shown that the Wufeng-Longmaxi formations of the Anchang syncline are superior in geological conditions and have good prospects for shale gas exploration.