Negatively charged liposomes prepared by solvent evaporation method were characterized by transmission electron microscopy, Raman spectroscopy and differential scanning calorimetry. The adsorption of Ni(II), Cd(II) and Hg(II) on the liposomes was systematically investigated. Special attention was paid to the effect of pH, ionic strength and the particle size of liposomes on the adsorption behavior. The increase of pH (from 6.5 to 8.1) enhanced the adsorption capacity (Qe) of three metals due to its effect on metal ions speciation and the conformation of polar phosphatidyl groups (active sites) on the liposome surfaces. The presence of ions slightly weakened the Qe of Ni(II) (p>0.05) and Cd(II) (p<0.05); while for Hg(II) adsorption at higher ionic strength (0.5mol/L), obvious stratification and precipitation was observed. Particle size of liposomes also influenced the adsorption process. Specifically, smaller unilamellar liposome vesicles after extrusion were more beneficial to the adsoprtion of Hg(II) (p<0.01); while larger multilamellar vesicles carried more negative charges benefit the adsoprtion of Ni(II) (p<0.01) and Cd(II) (p<0.05) rather than smaller unilamellar vesicles. Additionally, the sudden rises of the adsorption amount were observed for Cd(II) and Hg(II) and to a less extent for Ni(II), probably because of the changes of the structures or properties of liposomes, i.e., the fusion of vesicles, in the presence of high concentration of heavy metals.