A kit for preparing a radiolabeled liposome is provided, the kit including a liposome suspension and a radionuclide, wherein the liposome suspension includes a conjugate with a structure of [chelator-hydrophilic polymer-lipid]. A method for preparing a radiolabeled liposome using the kit is also disclosed herein, thereby the radiolabeled liposome being produced with the conjugate connected to the surface therein. The advantages of the present disclose such as simple, convenient and without purifying for the produced radiolabeled liposome are thus achieved. Further, the produced radiolabeled liposome has a high specific activity and a high sensitivity and suits for the clinical use.