There are two viewpoints about the genesis of dissolution pore in deep marine carbonate rocks in Northeast Sichuan as follows: (1) Early meteoric water and shallow burial dolomitization; (2) Late burial dissolution of fluid. Through in-situ simulations and experiments on Permian samples,it shows that with the increase of depth and temperature, calcite and dolomite are tend to be cement rather than dissolution, and the calcite cement is of greater extent. Therefore, the possibility of deep dissolution is few, while the early diagenesis is the key to the formation of secondary dissolution. The sedimentary facies of marine strata and the evolution law of secondary pores in deep burial stage should be further explored.