Venous thromboembolism (VTE) is one of the complications which have significant influence on mortality in patient with cancer. Early mortality rate is high in cancer patients who have VTE. This complication is related with cell type and stage of the cancer, surgery applied during cancer treatment, applying catheter and the chemotherapeutic agents. VTE prophylaxis and/or treatment in treatment and follow-up of cancer patients will provide a reduction in mortality and morbidity rates. VTE prophylaxis and treatment poses differences according to both treatment approaches which will be applied and the type of cancer. It has been aimed to describe pathogenesis, risk factors and treatment approaches taking into account international consensus reports in this review.