Transformer

The present invention provides a transformer which comprises the following components: a main coiling; a plurality of conducting pieces; a coiling base which comprises a plurality of hollow spacing plates and a plate piece which is arranged between two adjacent hollow spacing plates and is used for forming a through channel and a coiling groove that is used for coiling the main coiling, and each hollow spacing plate is provided with an accommodating groove that is used for accommodating at least one conductive plate; and a magnetic core group which is partly arranged in the through channel. The transformer of the invention has the advantages of simple structure, easy installing and better operating performance. A first extending part of the conducting piece can be used for assisting the fixing and/or heat radiating of the electronic element thereby reducing the using amount of other fixing component to increase the space usage factor of the circuit board.