PURPOSE: A transformer and a power module having the same are provided to make a transformer having a new winding structure capable of coping with a surge voltage without needing to add additional elements. CONSTITUTION: A bobbin (10) has a plurality of winding spaces formed on an outer circumferential surface of a cylindrical body portion thereof. The bobbin includes a winding unit having the plurality of winding spaces in which coils (50) are wound and a terminal fastening unit (20) formed at one end of the winding unit. The terminal fastening unit has a primary terminal fastening unit (20a) and a secondary terminal fastening unit (20b). An external connection terminal (30) is fastened to the terminal fastening unit in a protruding manner. A core (40) is inserted into a through hole formed within the body of the bobbin to form a magnetic path electromagnetically coupling to the coils.
