Disclosed in the present invention is the use of a water soluble platinum complex in preparing drugs for the prevention and treatment of tumors, said platinum complex being shown as formula (I). Experiments have demonstrated that the present water soluble platinum complex alone or in combination with other chemotherapeutics is able to treat cancer in mammals, and in particular, humans, said cancers including lung cancer, colon cancer, head and neck cancer, prostate cancer, breast cancer, ovarian cancer, cervical cancer, leukemia, lymphoid cancer, skin cancer, pancreatic cancer, liver cancer, bladder cancer, esophageal cancer, gastric cancer, male genital cancer or bone cancer.
