Disclosed a bi-directional blender, comprising a cup and a cap holder rotatably connected with the cup by a threaded flange, wherein the interior of the cup is a cavity in which a first blending blade and a second blending blade are fixedly mounted. In the bi-directional blender of the invention, the cup is internally provided with the first blending blade and the second blending blade, the two sets of blending blades may rotate in opposite directions to form a forward and a reverse crushing structure capable of better crushing all kinds of ingredients, and thus the blender can be used in a juicer and a food processor.