In order to clarify the reservoir applicability of different acid systems, understand the influence of reservoir acid rock etching morphology on fracture conductivity, and give the optimal slug combination method for different horizons, acid erosion fracture conductivity experiments were carried out in the carbonate reservoirs of Sichuan and Chongqing, the results show that the conductivity of slug combinations between different acid systems to the dolomite of the Maokou Formation after acid etching is higher than that of the limestone. The morphology of acid-etched fractures after acid-etching is different between different single-acid systems, in which steering acid has extremely deep grooves after etching, and the grooves of authigenic acid are the shallowest. For Maokou Formation, when the alternation between gelling acid and fracturing fluid and the alternation between gelling acid and authigenic acid is tertiary, the conductivity is the highest, and the conductivity reaches 4.53 μm²·cm at 60 MPa after tertiary alternation between gelling acid and authigenic acid. The conductivity of Qixia Formation and Dengying Formation is the highest when secondary alternation of fracturing fluid and gelling acid was selected, and the conductivity of Qixia Formation and Dengying formation are 6.72 μm²·cm and 7.47 μm²·cm at 60 MPa, respectively. In the Sichuan Chongqing exploration area, on-site application and in-depth investigation were conducted to verify the acid corrosion fracture conductivity of the acid solution. The results show that the acid corrosion effect is good after the acid solution entered the well, and the gas testing effect after the transformation is 208 × 10⁴ m³/d, achieving the expected increase in production. It provides theoretical and experimental guidance for acid fracturing technology of carbonate reservoirs in Sichuan and Chongqing.