A neutron capture therapy system, including a beam shaping assembly, and a vacuum tube and at least one cooling device. The beam shaping assembly includes a beam inlet, an accommodating cavity accommodating the vacuum tube, a moderator adjacent to an end portion of the accommodation cavity, a reflector surrounding the moderator, and a radiation shield and a beam outlet arranged in the beam shaping assembly. An end portion of the vacuum tube is provided with a target. The cooling device undergoes a nuclear reaction with a charged particle beam incident from the beam inlet to produce neutrons. The moderator decelerates the neutrons produced by the target to an epithermal neutron energy region. The reflector leads deviating neutrons back to the moderator. At least one accommodating pipeline accommodating the cooling device is arranged in the beam shaping assembly. A filler is filled between the cooling device and the accommodating pipeline.