Abstract: As oil sands are characterized by shallow burial and high viscosity, its exploration and evaluation methods are different from those of conventional oil and gas. Technologies of small spacing hole drilling and full hole-section coring are used to recognize oil sands, and the effective thickness and reserves are determined on the basis of crude oil mass percentage of oil sands, based on which the exploration and evaluation are carried out for oil sand ores in Fengcheng area of Junggar basin. Selecting a fault block and using 2 exploration methods of hole drilling and well drilling, the comparison analysis shows that the effective thicknesses determined by the 2 methods are congruent and the reserves calculation results are close to each other