In order to study the mechanism of carbonate rocks dissolution in organic acid under the conditions from epigenesist to deep burial digenesis environment, the reactions of acetic acid (initial 0.2,) with six types of carbonate rocks were investigated using two experimental ways of surface dissolution and internal dissolution. The result of surface dissolution indicates that dissolution rates of carbonate rocks increase with increasing the temperature and pressure. In the conditions from epigenesis to middle burial digenesis environment, the dissolution rates of marl and bioclastic wackestone are twice or three times than that of fine crystalline dolostone. In the condition of deep burial environment, the dissolution rates of bioclastic wackestone, marl, and fine crystalline dolostone are basically the same. The result of internal dissolution shows that the dissolving capacity of dolomitic grainstone in acetic acid is greater than that of microcrystalline to fine crystalline dolostone and sparry oolitic dolostone in the conditions at 60 ℃ and 10MPa. The dissolving capacity of dolomitic grainstone, microcrystalline to fine crystalline dolostone and sparry oolitic dolostone increases with increasing temperature and pressure in acetic acid. When the temperature and pressure reach to or exceed 90 ℃ and 20 MPa, the dissolving capacity in acetic acid of microcrystalline to fine crystalline dolostone and sparry oolitic dolostone is greater than that of dolomitic grainstone. Based on the results of experiments, it can be predicated that the dissolution rate and solubility of limestone in organic acid is greater than that of dolostone under the conditions of epigenesist and relatively shallow burial environment, so that the dissolution capacity of limestone must be greater than that of dolostone. Under the deep burial condition, dolostone has greater dissolution capacity and the similar dissolution rate with limestone. This maybe is one of the most important reasons why dolomite reservoirs with secondary porosity are more than limestone reservoirs in relatively deep strata.