The microencapsulation vesicle (MCV) method used for liposome preparation that reproducibly produces liposomes with homogeneous particle sizes with a high encapsulation efficiency. Liposomes encapsulating water-soluble drugs, lipophilic drugs and an amphiphilic drug are prepared by above method.  Encapsulation efficiency of the drugs is examined by using three kinds of egg yolk lecithin with different iodine values, i.e., purified egg yolk lecithin (PEL), partially hydrogenated purified egg yolk lecithin (R-20) and completely hydrogenated purified egg yolk lecithin (R-5),are used for membrane materials in order to explore the possible effects of membrane rigidity or surface area on the encapsulation efficiency of the drug. Water-soluble 5-fluorouracil shows 12-15% encapsulation efficiency. drug-containing water phase was always separated from the dispersion medium by the lecithin-containing oil phase, which was advantageous to maintaining a higher encapsulation efficiency of the water-soluble drug. The encapsulation efficiency of lipophilic ibuprofen and flurbiprofen remain around 90%. As for ketoprofen and liposomes are not formed when using hydrogenated egg yolk lecithin R-5, while the encapsulation efficiency using PEL or R-20 is obtained around 80%. Amphiphilic amitriptyline hydrochloride resulted in a slightly higher encapsulation efficiency when dissolved in the water than the chloroform. Among the three kinds of lecithin, the most unsaturated PEL tended to show a higher encapsulation efficiency, probably due to differences in the packing geometry of the hydrophobic carbon chains in the membrane bilayer. The encapsulation efficiency of these drugs strongly correlated to the logP(octanol/water) and also tended to correlate to the logP(chloroform/water) for the order of the logP(chloroform/water) remains almost the same as the order of the logP(octanol/water) in the drugs examined.