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We report a study of enhancing the magnetic ordering in a model magnetically doped topological insulator (TI), Bi[subscript 2–x]Cr[subscript x]Se[subscript 3], via the proximity effect using a high-T[subscript C] ferrimagnetic insulator Y[subscript 3]Fe[subscript 5]O[subscript 12]. The FMI provides the TI with a source of exchange interaction yet without removing the nontrivial surface state. By performing the elemental specific X-ray magnetic circular dichroism (XMCD) measurements, we have unequivocally observed an enhanced T[subscript C] of 50 K in this magnetically doped TI/FMI heterostructure. We have also found a larger (6.6 nm at 30 K) but faster decreasing (by 80% from 30 to 50 K) penetration depth compared to that of diluted ferromagnetic semiconductors (DMSs), which could indicate a novel mechanism for the interaction between FMIs and the nontrivial TIs surface., State Key Programme for Basic Research of China (Grant 2014CB921101), National Natural Science Foundation (China) (Grant 61274102), Science and Technology Facilities Council (Great Britain), United States. Defense Advanced Research Projects Agency. Meso Program (Contract N66001-12-1-4034), United States. Defense Advanced Research Projects Agency. Meso Program (Contract N66001-11-1-4105)