Clinical studies have shown that malignancy is an important cause of deep vein thromboembolism (including pulmonary artery embolism) that cannot be ignored. About 19%-30% of patients with deep vein thromboembolism (VTE) have malignant tumors, and the proportion of patients with tumors as the primary disease in patients with VTE of unknown origin is even higher than the above data. In patients with malignant tumors, prolonged bed braking due to long-term indwelling intravenous catheters, aggravated symptoms, and the hypercoagulable state of the blood due to the tumor itself can lead to VTE. some studies have pointed out that VTE and tumor interact with each other, and the occurrence of VTE is positively correlated with the malignancy of the tumor, tumor load and length of hospital stay, and VTE is also an independent predictor of all-cause mortality in patients with tumors. Numerous studies have shown that overall mortality, VTE recurrence rate, and bleeding events are significantly higher in tumor patients with combined VTE than in concurrent tumor patients without VTE. However, the specific site of VTE (e.g., lower extremity, upper extremity, or pulmonary vascular) was not significantly correlated with the prognosis of the tumor. For the prevention of tumor-derived VTE, prophylactic anticoagulation with low molecular weight heparin (LMWH) or plain heparin is currently advocated routinely for oncology patients during hospitalization. For oncology patients who will undergo surgery, prophylaxis with LMWH should be started at least 12 hours before to 2 hours before surgery, and after surgery, a daily dose of LMWH strategy should be used for a minimum duration of 7-10 days. For oncology patients undergoing abdominal surgery, including laparoscopy, an extended prophylaxis regimen of up to 4 weeks is recommended if the risk of bleeding is not high. Also, the use of mechanical compression (compression stockings or intermittent compression pumps) alone to prevent VTE is not recommended unless the patient is evaluated as a contraindication to pharmacologic anticoagulation. Anticoagulation should be implemented in patients receiving chemotherapy, especially in patients with progressive or metastatic pancreatic and lung cancer, because of their propensity for blood hypercoagulation, but the possible effects of certain chemotherapeutic agents on systemic coagulation should be taken into account. Compared with non-oncologic VTE patients, oncologic patients with concomitant VTE still have a significantly higher recurrence rate of VTE and serious bleeding events even if they receive the same anticoagulation therapy, which makes antithrombotic therapy for VTE of tumor origin more complicated. It is currently advocated to divide antithrombotic therapy for such patients into two phases: early initial intervention and long-term maintenance intervention, and to prefer to continue LMWH rather than warfarin maintenance therapy after early LMWH anticoagulation. One study showed that long-term treatment with LMWH did not increase the risk of bleeding and the risk of VTE recurrence was reduced by 50% compared with warfarin regimen. In conclusion, the diverse and insidious clinical symptoms of tumor-derived VTE are easily masked by other comorbidities. Clinicians should improve their comprehensive understanding of this disease and consciously carry out the diagnosis and treatment of VTE along with the diagnosis and treatment of the primary disease, so as to strive for early diagnosis and treatment for tumor patients.