In order to improve the flux and the quality of a neutron source, provided are beam shaping bodies (60 and 70) for neutron capture therapy, wherein the beam shaping bodies (60 and 70) comprise beam inlets (61 and 71), targets (62 and 72), retarding bodies (63 and 73) adjacent to the targets (62 and 72), reflecting bodies (64 and 74) surrounding the outside of the retarding bodies (63 and 73), thermal neutron absorbers (65 and 75) adjacent to the retarding bodies (63 and 73), and radiation shields (66 and 76) and beam outlets (67 and 77) provided in the beam shaping bodies (60 and 70). A nuclear reaction occurs between t targets (62 and 72) and proton beams entering from the beam inlets (61 and 71), so as to produce neutrons. The neutrons form a neutron beam. The neutron beam defines main axes (X6 ad X7). The retarding bodies (63 and 73) slow down the neutrons produced by the targets (62 and 72) when arriving at an epithermal neutron energy region. The retarding bodies (63 and 73) are designed to be in a shape containing at least one cone. The retarding bodies (63 and 73) have main bodies (631 and 731) and replenishing portions (632 and 732) surrounding the outside of the main bodies (631 and 731). The material of the replenishing portions (632 and 732) is different from that of the main bodies (631 and 731). The reflecting bodies (64 and 74) guide the neutrons deviating from the main axes back to the main axes (X6 and X7), so as to increase the strength of the epithermal neutron beam. The thermal neutron absorbers (65 and 75) are used for absorbing thermal neutrons, so as to prevent the thermal neutrons from causing an excessive dosage for a superficial normal tissue during therapy. The radiation shields (66 and 67) are used for blocking leaking neutrons and photons, so as to reduce the normal tissue dosage of a non-irradiated region.L'invention vise à améliorer le flux et la qualité d'une source de neutrons, grâce à des corps de mise en forme de faisceau (60 et 70)
