In order to improve the flux and the quality of a neutron source, provided is a beam shaping body (60) for neutron capture therapy, wherein the beam shaping body (60) comprise beam inlet (61), target (62), moderator (63) adjoining to the target (62), reflector (64) surrounding the outside of the moderator (63), thermal neutron absorber (65) adjoining to the moderator (63), and radiation shield (66) and beam outlet (67) provided in the beam shaping body (60). A nuclear reaction occurs between target (62) and proton beams entering from the beam inlet (61), so as to produce neutrons. The neutrons form a neutron beam. The neutron beam defines main axe (X6). The moderator (63) slows down the neutrons produced by the target (62) when arriving at an epithermal neutron energy region. The moderator (63) is designed to be in a shape containing at least one cone. The moderator (63) has main body (631) and supplement section (632) surrounding the outside of the main body (631 and 731). The material of the supplement section (632) is different from that of the main body (631). The reflector (64) guide the neutrons deviating from the main axe back to the main axes (X6), so as to increase the strength of the epithermal neutron beam. The thermal neutron absorber (65) is 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 shield (66) is used for blocking leaking neutrons and photons, so as to reduce the normal tissue dosage of a non-irradiated region.
