Abstract: The mechanical and geoenvironmental characteristics of the improved Xiaoshan clay mixed with tung oil and sticky rice juice were investigated.Tung oil with the performance of seepage prevention,strong adsorbability,acid/alkalescence-resistant,water-resistant and sunproof and sticky rice juice with high glutinousness,low expansibility and good tenacity were selected as the additives.From permeability tests,shearing tests,adsorption tests and diffusion tests,it was shown that when the mass ratio of the soil,sticky rice juice and tung oil was 90∶5∶5,the mixed soil had lower coefficient of permeability than crude soil by 2 orders of magnitude.Meanwhile,the adsorption capacity of the mixed soil for metal cation distinctly increased,especially for Cu2+.Morphological microstructure of the mixed soils was studied by scanning electron microscopy(SEM).Tung oil could scatter and penetrate into pores between the soil particles or slices and form solid tenacious polymer film that was strongly bonded to the surface of Xiaoshan clay.It was indicated that better mechanical and geoenvironmental characteristics would be obtained by mixing the clayey soil with tung oil and sticky rice juice.