The \({\text{T}}_{2} {\text{l}}_{3}^{4}\) grained dolomite reservoir is well developed in the Middle Triassic Leikoupo Formation, Longgang area, central Sichuan Basin. The complex lithology of this reservoir, with strong longitudinal and transversal non-homogeneity, and the evaluation of reservoir validity has always been a key research point in the area, so it is very important to figure out the characteristics of the distribution of this reservoir and its controlling factors, and it will greatly expand the field of exploration of the Leikoupo Formation in the Sichuan Basin. The flow of quantitative identification and evaluation of Reservoir: ① based on the data of core, thin section, logging and seismic, the mineral composition, lithology and lithofacies identification model of Dolomite Reservoir is established, the characteristics of lithology and lithofacies of single well reservoir are implemented, and the sedimentary microfacies and effective reservoir distribution are studied; ② the analysis of seismic response characteristics of favorable reservoirs shows that the root mean square amplitude (rms) attribute is sensitive to \({\text{T}}_{2} {\text{l}}_{3}^{4}\) reservoir in Longgang area, and the seismic reflection of peak-trough is moderate and weak, through seismic attributes and palaeogeomorphology qualitative prediction of reservoir distribution characteristics; ③ waveform indication inversion, geostatistical inversion and other multi-inversion techniques are combined to quantitatively predict the distribution characteristics of favorable reservoir thickness. The research results show that the distribution of \({\text{T}}_{2} {\text{l}}_{3}^{4}\) grain beach dolomite reservoir is controlled by sedimentary facies belt, palaeogeomorphology and supergene karstification after Indosinian uplift, the favorable reservoirs are mainly developed in the high area of Pangu structure on the fault of LG22-LG161 area.