Comprehensive treatments for visceral metastatic carcinoma of unknown primary site (VMCUP) including surgery and chemotherapy significantly improved patients’ overall survival time. Patients treated mainly by surgery lived longer than those treated by chemotherapy alone. More chemotherapy cycles resulted in longer survival time for patients only receiving chemotherapy. For the first time, this study identified paclitaxel plus fluorouracil as more effective first-line chemotherapy drugs than 5-fluorouracil in treating VMCUP.