The present disclosure provides a neutron capture therapy system, including a neutron generator to generate neutrons after irradiation by charged particles, and a beam shaping assembly includes a moderator and a reflector surrounding the moderator. A vacuum tube connected to the accelerator is provided at an accommodating portion. The vacuum tube transmits the charged particles accelerated by the accelerator to the neutron generator to generate neutrons. The neutron generator moves between a first position and a second position, at the first position, the neutron generator react with the charged particle beam to generate neutrons, at the second position, the neutron generator falls off the beam shaping assembly. The vacuum tube is detached to make the neutron generator fall off the beam shaping assembly, to reduce direct contact of a worker with the neutron generator after nuclear reactions, thereby reducing radioactive hazards for workers.
