Background: Venous thromboembolic event (VTE) is a common complication for cancer patients, leading to hospitalizations that increase the burden of cancer management. We evaluated the incidence and costs of VTE-related hospitalizations for patients with breast or prostate cancer, two of the most frequent cancers in France. Methods: We used the French national hospital database (PMSI) to select new patients with BC or PC in 2010, who had at least one VTE-related hospitalization during the following two years. VTE-related stays and patients were identified using the disease-specific ICD-10 codes. Hospital costs were estimated from the healthcare system perspective and included care, treatments, accommodation/investment costs and medical/technical procedures, using the French official tariffs. Results: Among 107,916 new patients with BC or PC, 2,268 were hospitalized for a VTE, representing an overall of 2,814 admissions. VTE was classified as primary or related diagnosis (PD/RD) in 1,004 (36%) admissions. Among those PD/RD admissions, pulmonary embolism was the most frequent diagnosis as it led to 626 (62%) stays. Deep venous thrombosis was the second cause of hospitalization (248 admissions; 25% of PD/RD admissions). Re-hospitalisation for recurrence was frequent, as it occurred 546 cases (19.4%) of all VTE-related hospitalizations. For a patient who did not experience recurrence, the mean cost per patient was €3,302 and €3,611 for BC and PC patients respectively. But this amount was highly increased for patients with recurrent VTE, to €5,545 per BC patient and €5,692 per PC patient. Finally, VTE-related hospitalizations were responsible for an overall expenditure of €3.40 million over two years, including €335,000 due to recurrent events. Conclusions: In cancer patients, VTE-related hospitalizations remain frequent and induce an elevated cost. Adequate prophylaxis and management could be an efficient way to reduce the incidence of this common complication and its economic burden.