Abstract: Based on investigation, adopting clay, diatomite, vermiculite powder and Nochar as absorbent of oil, the capability of absorbent were studied. The result shows that optimum bonding ratios (oil﹕absorbent) are 0.316﹕1, 1.079﹕1, 1.196﹕1 and 2.0﹕1 respectively; oil leaching rates are 2.099%, 8.15%, 3.90% and 0.028% respectively; volume expansions are 398%, 266%, 312% and 437%, respectively. So, Nochar is a favourable absorbent for treating high-radioactivity pump oil, lennilite and clay are favourable absorbents for treating low-radioactivity pump oil.