Direct　X-ray　detectors,which　directly　convert　X-rays　into　electrical　signals　through　semiconductors,have　higher　space　solution　than　scintillator-mediated　indirect　X-ray　ones　and　are　high　desirable　for　early　cancer　detection　and　other　applications,but　the　mainstream　commercial　α-Se　detector　is　still　largely　limited　by　high　production　costs,large　leakage　current　and　low　stability.This　article　reports　an　eas-ily　prepared,stable　radiochromic　semiconductive　metal-organic　framework(MOF),(MV)[Cd3(tdc)4]-2H2O(RCS-1,H2tdc=2,5-thiophenedicarboxylic　acid;MV2+=methyl　viologen　cation)with　direct　X-ray　de-tecting　ability.With　a　large　bulk　resistivity　of　8.40　×　109　Ω　cm,this　material　ensures　minimal　dark　current　and　low　noise　for　X-ray　detection.Additionally,it　exhibits　higher　sensitivity　to　W　Kα　X-rays(98.58　μC　Gy-1　cm-2)than　α-Se(～20　μC　Gy-1　cm-2).Meanwhile,unlike　most　reported　direct　X-ray　de-tecting　semiconductors,compound　RCS-1　shows　remarkable　color　change　upon　X-ray　irradiation　owing　to　the　presence　of　photochromism-active　viologen　cations.This　feature　offers　an　appealing　visual　detecting　ability　to　direct　X-ray　detectors　that　provide　only　the　electrical　signals.