The present invention relates to a drug delivery vehicle comprising a polydiacetylene liposome, wherein a lipid bilayer is formed by a mixture of 10,12-pentacosadiynoic acid (PCDA), 1,2-dioleoyl-sn-glycero-3-phosphoethanolamine (DOPE), and N-palmitoyl homocysteine (PHC), and a drug to be delivered is encapsulated in an isolated inner space of a polydiacetylene liposome. The PDA liposome drug delivery vehicle of the present invention comprises a lipid layer formed by mixing different phospholipids, excluding polydiacetylene, so as to be stable, and thus any leakage problems of an encapsulated drug are eliminated. In addition, since the liposome is sensitive to a pH, the shape and size thereof can be readily changed through the formation of a liposome-liposome conjugate by the improved sensitivity of the drug delivery vehicle under a specific acidic requirement, thereby enabling selective drug release, and thus can be applied as a drug delivery vehicle for various target materials. Additionally, the release of a drug can be controlled by controlling a pH requirement of the surroundings, and a drug release process can be monitored in real time through the fluorescence expressed by the stimulation to the surroundings.