The invention discloses an integrated transformer. The integrated transformer comprises magnetic cores and coils; the magnetic cores comprise a transformer magnetic core, an inductor magnetic core anda common magnetic core, wherein the transformer magnetic core and the inductor magnetic core are arranged oppositely, and the common magnetic core is arranged between the transformer magnetic core and the inductor magnetic core; the coils comprise a primary coil, a secondary coil and an inductor coil, wherein the primary coil and the secondary coil are arranged between the transformer magnetic core and the common magnetic core, and the inductor coil is arranged between the inductor magnetic core and the common magnetic core; partition plates are arranged between the magnetic cores and the coils, and partition plates are arranged among the coils. The integrated coil has the advantages of not only effectively reducing the production cost, reducing the size of components and increasing the power density of a switch power source, but also having convenient production and high universality.