A novel integrated magnetic structure suitable for the transformer-linked interleaved boost chopper circuit is proposed in this paper. The coupled inductor is known to be effective for miniaturization in high coupling area because the DC flux in the core can be canceled and the inductor current ripple become to high frequency. However, coupled inductor with E-E core and E-I core are realistically difficult to obtain necessary leakage inductance in high coupling area. The cause is fringing effect and the effects leads to complication of magnetic design. To solve this problem, novel integrated magnetic structure with reduction of fringing flux and high frequency ripple current performance, is proposed. Furthermore, the design method for novel integrated magnetic structure suitable for coupled inductor is proposed from analyzing of the magnetic circuit model. Finally, effectiveness of reduction of fringing flux and design method for novel coupled inductor are discussed from experimental point of view.