Oil sand cores tend to expand when they are recovered from deep heavy oil formations. Computer tomography scans of these cores show that discrete tensile fractures are induced within the cores. Formation of these fractures is attributed to the gas nucleation and exsolution process in the viscous heavy oil under the overburden stress relief in coring and retrieval. In core tubes with perforated holes, the core dilation depends on the clearance gap between the inner diameters of the core barrel and core tube. This paper proposes a recompaction method to restore these dilated cores to a state close to its initial porosity (some of locked structure may not be recovered). Geotechnical and hydraulic tests along with computer tomography imaging technique were conducted on these recompacted core specimens. Test results of the recompacted specimens were compared to those of the intact and reconstituted specimens to illustrate the effectiveness of this recompaction method.