Organic　scintillators,　pivotal　in　security　and　medical　applications,　face　challenges　due　to　limited　X‐ray　absorption　and　exciton　utilization.　Herein,　a　novel　class　of　organic　scintillators　is　introduced,　named　guest‐induced　thermally　activated　delayed　fluorescence　(TADF)　within　supramolecular　macrocycles　via　host‐guest　through‐space　charge　transfer　(TSCT).　Four　co‐crystals　are　obtained　through　orthogonal　crystallizations　involving　calix[3]acridan　(C[3]A)　and　calix[3]phenothiazine　(C[3]P)　macrocycles　as　hosts,　along　with　1,2‐dicyanobenzene　(DCB)　and　4‐bromo‐1,2‐benzenedicarbonitrile　(BrDCB)　as　guests.　Interestingly,　DCB@C[3]A　and　BrDCB@C[3]A　co‐crystals　exhibit　strong　host‐guest　TSCT　with　reduced　single‐triplet　energy　gap　for　efficient　TADF　emission,　which　leads　to　enhanced　exciton　utilization　and　X‐ray　absorption,　yielding　radioluminescence　intensities　over　29　and　25　times　higher　than　C[3]A.　Similarly,　substituting　C[3]A　with　C[3]P,　the　obtained　TADF　co‐crystals　also　outperform　C[3]P　in　scintillation　performance.　Additionally,　the　scintillation　color　of　co‐crystals　can　be　adjusted　by　varying　the　electron‐donating　abilities　of　macrocycles　and　the　electron‐accepting　abilities　of　guests,　offering　a　simpler　color‐tuning　mechanism　than　covalent‐bonded　scintillators.　Furthermore,　the　flexible　film　based　on　DCB@C[3]A　exhibits　promising　application　in　X‐ray　radiography,　showcasing　a　high　spatial　resolution　of　20　lp　mm−1　@MTF　=　0.77.　The　innovative　strategy　of　fabricating　organic　scintillators　via　reversible　non‐covalent　interactions　presents　a　novel　solution　for　designing　color‐tunable　and　high‐performance　scintillators.