In this paper, an interleaved high step-up DC-DC converter with winding-cross-coupled inductors is presented. Firstly, the second winding of each coupled inductor is connected with a capacitor, which composes a quasi voltage multiplier unit (QVMU). Then, a boost circuit consists of the QVMU, the primary winding and the main switch. Moreover, the QVMU can be charged through the clamp capacitor and the third winding of the other phase coupled inductor. Thus, two phases can be cross-coupled. Furthermore, the primary currents of two coupled inductors are interleaved in parallel at input. There are many advantages of the above-mentioned structure. Firstly, the proposed converter can be operated in the duty cycle of the entire range of variation and the expression of the voltage gain can be consistent across the range of the duty cycle. Secondly, the output voltage and input current of each phase can be automatically regulated to be equally distributed. Thirdly, the proposed converter can achieve a high step-up voltage conversion and the voltage stress on the power devices can be reduced. Lastly, a high step-up gain can be flexibly adjusted. The operating principle of the proposed converter is analyzed. In order to verify the theoretical analysis, an experimental prototype is built.