A neutron capture therapy system includes a neutron beam generating unit, an irradiation room configured to irradiate an irradiated body with a neutron beam, a preparation room configured to implement preparation work required to irradiate the irradiated body with the neutron beam, and an auxiliary positioner disposed in the irradiation room and the preparation room. The irradiation room comprises a first shielding wall, a collimator is disposed on the first shielding wall for emitting the neutron beam. The neutron beam is emitted from the collimator and defines a neutron beam axis. The auxiliary positioner comprises a laser emitter that emits a laser beam to position the irradiated body. Wherein the position of the laser emitter is selectable. Therefore, the irradiated body can be positioned in any case to implement precise irradiation.
