Provided is a liposome useful as a vaccine adjuvant. More specifically, provided is a liposome which comprises a lipid bilayer containing dimyristoylphosphatidylcholine and egg phosphatidylglycerol and a conjugate compound in which a low-molecular weight compound enhancing the physiological activity of TLR7 is bound to squalene via a linker, said conjugate compound being encapsulated in the lipid bilayer.
