A hanging electronic device, for hanging on a H thickness wall, comprises a main body and an adjustable hanging mechanism. The adjustable hanging mechanism for mounting the main body on the wall comprises: at least one cantilever bar and an elastic member. The cantilever bar has a first rod, a second rod, a third rod and an elastic member. The first rod has a rotation axis for the cantilever bar to rotate on the main body, and the second rod is coupled to the first rod. The third rod coupled to the second rod is substantially parallel to the first rod. The elastic member is coupled to the first rod. When the cantilever bar rotates relatively to the main body with a rotation angle α, the third rod is firmly against the wall.