Abstract: Aiming at the carbonate rockⅠ, Ⅱ, Ⅲ reservoirs in Gao-Mo block Dengying formation of Sichuan Basin, and on the basis of analyzing experimental results of the peak viscosity, the double core acidification effect and the steering pressure, it is clear that the high acid concentration variable viscosity steering acid has a better steering effect for the class Ⅱ and Ⅲ reservoirs, the maximum steering pressure is 10 MPa in field test; the low acid concentration visbreaking type acid has a better steering effect for class Ⅰ reservoir, and the maximum steering pressure is 12 MPa in the site test.