Electronic and information hardware is developing in the direction of lightweight products, miniaturization, and integration. The transformer is still the most effective solution for signal isolation and power transfer. In response to the key problems of microtransformer fabrication, this paper presents a hybrid method for fabricating micro/nano structures via femtosecond laser wet etch technology and liquid metal microinjection. This research aims to develop a new method of creating an integrated microtransformer, offering an effective solution for the fabrication of widely applicable 3D integrated complex structures. The embedded 3D microtransformer can be easily integrated with other microelectrical, mechanical, and optical systems, with potential applications in MEMS, sensors and lab-on-chips.