The　weakness　of　visible　and　near-infrared　light　penetration　depth　limits　the　application　of　photodynamic　therapy　(PDT)　in　deep-seated　tumors.　Based　on　the　high　penetrability　of　X-rays,　X-ray-induced　PDT　(X-PDT)　is　a　promising　new　method　for　treating　deep-seated　tumors.　However,　it　requires　the　development　of　suitable　X-ray-induced　sensitizers　that　could　employ　X-ray　energy　to　produce　reactive　oxygen　species　(ROS)　efficiently.　In　this　study,　a　novel　X-ray-induced　sensitizer　(NanoSRF)　was　developed　through　a　microemulsion　method,　in　which　copper　iodine　cluster　compound　Cu2I2(tpp)2(2,5-dm-pz)　(CIP)　and　rose　bengal　(RB)　worked　as　scintillator　and　photosensitizer,　respectively.　CIP　was　synthesized　by　a　simple　mechanical　grinding　method,　and　subsequently　folic　acid　(FA)-modified　albumin　was　introduced　to　enable　its　alliance　with　RB.　NanoSRF　exhibited　excellent　dispersion　stability　and　generated　a　large　amount　of　ROS　under　X-ray　irradiation.　The　results　of　in　vitro　studies　demonstrated　its　high　selectivity　for　FA　receptor-positive　cancer　cells.　Following　systemic　administration,　NanoSRF　accumulated　in　H22　tumors　of　xenograft-bearing　mice,　and　X-ray　irradiation　(5.46　Gy)　induced　a　significant　inhibition　rate　of　96.7%　in　tumor　growth.　This　study　pioneers　the　use　of　copper　iodide　cluster　as　a　scintillator　in　X-PDT,　presenting　new　possibilities　for　designing　scintillators　with　exceptional　X-ray　absorption　and　efficient　X-PDT　capabilities.　(Figure　presented.)　©　Science　China　Press　2024.