LH-RH agonist is the key drug in hormonal therapy for premenopausal patients with breast cancer. It is important to reduce the pain related to injecting the LH-RH agonist, because patients must continue the medication for several years. We developed a way to reduce the pain by cooling the needle injecting site with a frozen ice pack. 18 premenopausal postoperated women filled out a questionnaire on the severity of pain upon injecting Goserelin acetate compared with the pain without this cooling method and pretreatment. We estimated the pain by a Numerical Rating Scale(NRS). The NRS scores of this cooling method revealed the pain to be significantly less than by control method(p<0. 005). This cooling method could be useful for the reduction of pain upon injecting the LH-RH agonist.