The utility model discloses a high -efficient oxidation unit of outer rotation of wet method flue gas desulfurization tower, including oxidation tower, agitator motor, oxidation air pipe, stirring drum, (mixing) shaft, agitator motor passes through the (mixing) shaft and is connected with the stirring drum, the stirring drum is porous cylindrical structure, the oxidation air pipe sets up in the oxidation tower bottom, oxidation air pipe one end is connected with oxidation air blower, the mouth of pipe of the oxidation air pipe other end extends to stirring drum center. In order further to improve effect of photocatalytic oxidation, proposed a high -efficient oxidation unit, the oxidation tower through independent setting can reduce the pH value in thick liquid pond, oxidation air passes through in the oxidation air pipe gets into the oxidation tower, oxidation air through with the stirring drum gassing that rubs rapidly, can mix more evenly with the thick liquid in the oxidation tower, stir the drum simultaneously and for the porous net column structure, can break up the bubble, make the bubble slighter, the mixed area of contact of increase.