A neutron capture therapy system in which space may be effectively utilized, a plurality of patients may be simultaneously treated, and a beam transmission path may not be excessively extended to ensure a small loss. The neutron capture therapy system includes an accelerator, a beam transmitting device, and a neutron beam generating device, wherein the accelerator is configured to accelerate charged particles to generate a charged particle beam, the beam transmitting device is configured to transmit the charged particle beam generated by the accelerator to the neutron beam generating device, and the neutron beam generating device is configured to generate a therapeutic neutron beam. The neutron beam generating device further includes a first neutron beam generating device, a second neutron beam generating device, and a third neutron beam generating device. The beam transmitting device further includes a first transmitting device connected to the accelerator, a beam direction conversion device configured to switch a traveling direction of the charged particle beam, and a second transmitting device, a third transmitting device, and a fourth transmitting device that respectively transmit the charged particle beam from the beam direction conversion device to the first neutron beam generating device, the second neutron beam generating device, and the third neutron beam generating device, wherein two of the first transmitting device, the third transmitting device, and the fourth transmitting device define a first plane, the first transmitting device and the second transmitting device define a second plane, and the first plane is different from the second plane.
