The present invention discloses a preparation method and uses of an anti-cancer drug estrogen targeting PEG-modified liposome. The liposome preparation method comprises: synthesizing estrone-pegylated phospholipid from activated estrone, taking 40-80 parts by weight of phospholipid, 5-45 parts by weight of cholesterol, and 5-40 parts by weight of pegylated phospholipid, dissolving in methanol, carrying out rotary evaporation, adding an ammonium sulfate aqueous solution, carrying out dialysis, adding 0.5-10 parts by weight of mitoxantrone, carrying out incubation, carrying out dialysis, adding 0.1-20 parts by weight of the estrone-pegylated phospholipid, carrying out incubation, and filtering with a membrane to obtain the liposome preparation. Compared with the liposome in the prior art, the obtained estrogen targeting PEG-modified liposome has characteristics of high encapsulation efficiency, uniform particle size, pharmacokinetics improving, anti-tumor efficacy enhancing, toxicity reducing, simple preparation process and easy scale-up production, and is expected to become the novel pharmaceutical preparation for cancer therapy. The uses are targeted treatments of breast cancer, leukemia and other cancers.