α-Mangostin is a product that is isolated from the mangosteen with diverse biological activities, including cytotoxicity against cancer cells. However, the drawback of this compound is its high cytotoxicity and poor solubility in water. In this study, α-mangostin-loaded liposomes are prepared to improve water solubility and reduce the side effects of α-mangostin in cancer treatment. The liposomal membrane consisted of soybean lecithin (Lec) and Cholesterol (Chol), at a molar ratio of 8/1. Experimental results show that liposomes fabricated in this way had a mean size of 115.5 nm, and a polydispersity index (PDI) of 0.122. The encapsulation efficiency of α-mangostin in liposomes is 50.3 %. Further, α-mangostin-loaded liposomes show lower cell viability than free α-mangostin. This formulation has expected the potential to be developed into an improved drug delivery system for αmangostin.