Based on the textural classification and oxygen isotope analyses, the temperatures of different types of dolomite samples from Feixianguan Formation of Northeast Sichuan Province are calculated by the dolomite-calcite oxygen isotope thermometer. Most of the calculated temperatures range over from 40 ℃ to 140 ℃. The calculated temperatures of crystalline dolomite and dolomite cement have a relatively high temperature range and the calculated temperatures of oolitic dolomite and micrite dolomite have a relatively low temperature range. These results are consistent with the fluid-inclusion homogenization temperatures and formation environment of dolomite.