Magnetic element, manufacturing method thereof and transformer

The embodiment of the invention discloses a magnetic element and a manufacturing method thereof and a transformer, the magnetic element comprises a first magnetic core, a second magnetic core, a framework, a winding and a first filling body, the first magnetic core comprises a first middle column, the first middle column comprises a first side surface, a second side surface and a third side surface, and the second side surface is opposite to the third side surface; and the two connecting rods are respectively connected to two opposite side edges of the first side surface. The second magnetic core is in butt joint with the first magnetic core. The framework is provided with a center hole, the first middle column penetrates through the center hole, and a first gap is formed between at least one side face of the first side face, the second side face and the third side face and the hole wall of the center hole. The winding is wound on the framework. The first filling body is filled in the first gap. 本发明实施例公开一种磁性元