This test was performed to evaluate the change of the unconfined compressive strength, strength parame­ters which resulted from direct shear test and oil residue percents analyzed by GC-MS as time lapse, oil addition. Unconfined compression strength of $10\%$ kerosene added by weight of dry soil recovered as time passed. In the case of $5\%$ kerosene added, the strength recovered as much as clean clayey soil after about 50 days passing. For the case of diesel added, the recovery of unconfined compressive strength was not shown even though about 60 days passed. The strength parameters (c, $psi$) of kerosene added not changed but for diesel added, the cohesion was very decreased as diesel addition increased. Residual percent of kerosene in the soil was less than that of diesel as time passed.