A biopsy device includes a first hollow cylindrical element, a second hollow cylindrical element inside which the first hollow cylindrical element is insertable and a locking element that is suitable for locking a tissue sample inside the first hollow cylindrical element. The locking element includes a deformable portion of the first hollow cylindrical element that is able to become deformed to enable a cross section of the first hollow cylindrical element to be closed, the deformable portion connecting a distal end of the first hollow cylindrical element to a body of the first hollow cylindrical element.