Abstract: The invention provides a device for the production, moderation and configuration of a neutron beam, comprising: an inlet opening (1) through which a proton beam is directed; a target (2) against which the proton beam is accelerated in order to generate neutrons; a moderator (3) to bring the neutrons to energies of the epithermal range; a reflective cover (4) surrounding the moderator (3); a filtration stage (5); an outlet opening (6) for the neutron beam, and a shield (7) to suppress the neutrons and gamma-radiation that do not exit the device via said outlet opening. The filtration stage (5) comprises at least three layers to filter respectively: rapid neutrons, thermal neutrons and gamma-radiation The invention is of use in neutron capture therapies, and more specifically, in boron therapies.