The deep marine carbonate gas reservoir plays an important role in increasing the reserve and production of conventional natural gas in Sichuan Basin. Qixia Formation in northwest Sichuan is an ultra-deep gas reservoir at a huge cost of development，so it is urgent to accurately evaluate the pore-throat structure of the reservoir and the production capacity of the block. However，we are now facing a lack of effective ways of precisely evaluating its diverse and multi-scale porethroat structure. To solve this，we made use of digital cores and high pressure mercury injection to work out a method for the evaluation of the complete micron-centimeter pore-throat structure of carbonate rocks. Then，we validated this method by laboratory seepage experiments and finally reached the following conclusions：①The correction of the capillary pressure curves obtained from high pressure mercury injection and the quantitative characterization of the vugs and macropores on the surface of rock samples by digital cores overcome the scale limitation of conventional high pressure mercury injection and can accurately evaluate the complete micron-centimeter pore-throat structure of carbonate rocks. ②This method results in wider pore-throat size distribution and higher sorting coefficients of rock samples from vuggy and fractured-vuggy reservoirs. The rock samples from fractured-vuggy reservoirs see obvious dual pore characteristics and great storage and seepage capacity，which are more consistent with basic physical properties of rocks. The complete pore-throat structure of Qixia Formation in Northwest Sichuan lays the groundwork for the high and stable production of gas wells，and finding fracture zones is the key to high production.