To provide a radiation intensity measuring apparatus for an encapsulated sealed radioactive source for brachytherapy, which can measure a plurality of cartridges efficiently and quickly. A device in which a plurality of sources S in seed cartridge SC of the cartridge C to measure the radiation intensity of the plurality of sources S in a state of being filled, the holding means 10 capable of holding a plurality of cartridges C, the plurality of sources the radiation intensity measuring means 30 for measuring the radiation intensity emitted from S, a moving means 20 for toward and away from the holding means 10 of the radiation intensity measuring means 30 has a radiation intensity measuring means 30, the radiation a sensor 31 for measuring the intensity, the shielding member 35 having a slit 35h provided so as to limit the radiation to be irradiated on the sensor 31 has a moving means 20, in the measurement state, a plurality of lines the source S is configured such that capable of relatively moving the radiation intensity measuring means 30 along a direction in a row.複数のカートリッジを効率良く迅速に測定することができるがん治療用密封小線源の放射線強度測定装置を提供する。 カートリッジCのシードカートリッジSCに複数の線源Sが充填された状態で複数の線源Sの放射線強度を測定する装置であって、カートリッジCを複数保持し得る保持手段10と、複数の線源Sから放出される放射線強度を測定する放射線強度測定手段30と、放射線強度測定手段30を保持手段10に対して接近離間させる移動手段20と、を備えており、放射線強度測定手段30は、放射線強度を測定するセンサ31と、センサ31に照射される放射線を制限するように設けられたスリット35hを有する遮蔽部材35と、を有しており、移動手段20は、測定状態において、複数の線源Sが並んでいる方向に沿って放射線強度測定手段30を相対的に移動させ得るように構成されている。
