Magnetic integration effectively reduces the total magnetic volume for a converter with multiple magnetic components. However, the existing solutions still face some problems, such as large core cross-sectional area due to the small effective inductor winding number or low PCB utilization due to unreasonable winding structure design. This paper proposed an integrated magnetic structure for the resonant inductor and transformer with a small core volume. By the proper winding arrangement, the integrated resonant inductor is constructed by both sides of the transformer windings, which not only increases the effective inductor winding number but also improves the utilization of the PCB. What is more, the inductor core plate and the transformer core plate are integrated, which further reduces the core size. Finally, a 2 kW CLLC prototype is established to verify the performance of the proposed integrated magnetics (IM) and its design methodology.