Abstract: The luntai fault is a large fault at Shaya uplift, Tarim basin, Xinjiang area, northwest China. It extends more than 280km from Bositan at the west to Kuerle at the east in a NEE to nearly EW direction. The fault is spade shaped with inclinations from 22°to 68°to north, steep at upper layers and gentle at deep layers. The fault is a typical large inverse thrust fault cutting many lavers from the Cambrain to the paleogene with maximum vertical fault throw of 4km. The fault is successive and experienced structural movements in different periods. It has controlled the evolution and formation of Yakela—Luntai faulted uplift, and created many oil and gas bearing structures. Many we11s were drilled at the banging side and some industrial standard oil and gas well were found. A few wells were drilled at the lower side but industrial standard oil and gas also found. In order to expand exploration field and investigate possible oil and gas distribution at the lower side of Luntai fault, the authors evaluate the sealing possibility of Luntai fault by using efficient seismic special processing methods and lithological prediction technologies. Based on the analysis of the structural characteristics of Luntai fault, we proposed technical methods for sealing analysis of the fault with geophysical methods. The methods are 1) seismic velocity inversion after carefu1 true amplitude seismic data processing; 2) calculation of the amount and distribution of clay, clay smears, porosity, pressure at both sides of the fault with seismic data and log data; 3) predicting sealing ability by comprehensive analysis of the relation of juxtaposition, permeability, c1ay sri1car potential, pressure difference: 4) evaluating oil and gas bearing possibility in Yanan No.1 structure on the data of seismic special processing and lithological predication.