Methotrexate has broad-spectrum antitumor activity and can be used alone or in combination with other chemotherapeutic agents. Generally its indications are still relatively broad. First, it can be used alone for antitumor therapy, such as breast cancer, choriocarcinoma, malignant hyperemesis or chylothorax. Second, it can also be used in combination with anti-tumor therapy, such as acute leukemia, Burkitt’s lymphoma, advanced lymphosarcoma, etc. Thirdly, it can be applied in high doses or in combination with other chemotherapeutic drugs to treat osteosarcoma, acute leukemia, bronchial lung cancer, or epithelial carcinoma of the head and neck, etc. When high-dose methotrexate is applied, formyl tetrahydrofolate must be applied for relief.