The limestone reservoirs of the Taiyuan Formation in the eastern Ordos Basin are characterized by complex geological features, including considerable burial depth, high in-situ stress, elevated formation temperature, strong heterogeneity, and well-developed micro-fracture systems. As a result, two major technical bottlenecks are encountered in reservoir stimulation: the rapid attenuation of diversion capacity in single acid fracturing and the difficulty in constructing complex fracture networks via single sand fracturing.To address these challenges, an integrated acid-fracturing with proppant technology was adopted in this study. A comprehensive experimental approach, combining rock mechanics testing, fracture conductivity evaluation, and CT scanning technology, was employed to systematically compare and analyze the conductivity performance and microstructural characteristics of three types of fractures, namely acid-etched fractures, proppant-supported fractures, and acid-fracturing with proppant composite fractures. Through this approach, the conductivity mechanisms and synergistic interaction mechanisms of the integrated acid-fracturing with proppant technology were clearly revealed.Experimental results demonstrate that the Taiyuan Formation limestone has a compressive strength ranging from 178 to 318 MPa and a Young's modulus of 32.4 to 45.1 GPa. After acid etching, the Young's modulus is reduced by 25.5%, indicating a significant rock softening effect. Under a closure pressure of 45 MPa, the conductivity of the acid-fracturing with proppant composite fractures reaches 54.9 μm2·cm, which is 1.5 times and 2.1 times that of acid-etched fractures and proppant-supported fractures, respectively.CT scanning results indicate that the composite fractures form a synergistic flow-conducting structure characterized by "acid-etched channels as primary flow paths and proppant providing support at contact points." After loading, the pore volume of the composite fractures decreases by only 17.5%, which is significantly lower than the reductions observed in acid-etched fractures (26.9%) and proppant-supported fractures (22.8%), demonstrating excellent structural stability.Finally, a predictive model for composite fracture conductivity was established based on the experimental data. This model accurately quantifies the influences of key parameters, including closure pressure, proppant concentration, and acid volume, on fracture conductivity, thereby providing crucial theoretical guidance for optimizing field operation parameters and achieving long-term efficient development of the reservoirs.