  The quantum anomalous Hall (QAH) effect have been experimentally observed in
magnetically-doped topological insulators. However, the QAH effect only at
extremely low temperatures due to the weak magnetic coupling, small band gap
and low carrier mobility. Here, based on first-principles density functional
theory, we predict that the Janus Mn2Cl3Br3 is high Curie temperature
ferromagnet that host the QAH phase. Furthermore, we find that it is a Dirac
half-metal characterized by a Dirac cone in one spin channel with carrier
mobilities comparable to freestanding germanene and an large band gap in other
spin channel. Simultaneously, when the spin-orbital coupling interaction is
considered, the Janus Mn2Cl3Br3 exhibit lager magnetic anisotropic energy of
11.89 meV/cell and a nontrivial band gap. More interestingly, both the Chern
number sign and the chiral edge current are tuned by changing the direction of
magnetization. Our finding would suggest the possibility of not only realized
the QAH effect but also designed the flow direction of the edge current.
