Abstract: This invention provides: 1) a method of treating androgen-deprivation induced osteoporosis and/or bone fractures and/or loss of Bone Mineral Density (BMD) in a male subject suffering from prostate cancer; 2) a method of preventing androgen-deprivation induced osteoporosis and/or bone fractures and/or loss of Bone Mineral Density (BMD) in a male subject suffering from prostate cancer; 3) a method of suppressing or inhibiting androgen-deprivation induced osteoporosis and/or bone fractures and/or loss of BMD in a male subject suffering from prostate cancer; and 4) a method of reducing the risk of developing androgen-deprivation induced osteoporosis and/or bone fractures and/or loss of BMD in a male subject suffering from prostate cancer, by administering to the subject a pharmaceutical composition comprising an anti-estrogen agent and/or its analog, derivative, isomer, metabolite, pharmaceutically acceptable salt, pharmaceutical product, hydrate, N-oxide, or any combination thereof.