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Wide voltage range converters are significant for photovoltaic power generation system, battery charging, and auxiliary power source, etc. Resonant converter has been preferred topology for these applications, however, some demerits exist: 1) difficult to realize wide voltage gain range and low circulating current losses; 2) widely regulated switching frequency to adapt to wide voltage gain range; and 3) poor regulation at light load. Based on abovementioned shortcomings, dual resonance core-based step-up/down switched capacitor converter topology is presented in this article. Utilizing hybrid control strategy, nonoverlapping control strategy is used in the buck-type mode and overlapping control strategy is applied in the boost-type mode with common switching frequency range, and therefore, reduced frequency range in the presented converter is achieved. Moreover, wide voltage gain range can be obtained due to step-up/down capacity in the proposed converter. Furthermore, conversion ratio of proposed converter can be reduced to zero theoretically by using dual resonance core existed in the resonant switched capacitor converter. Finally, comprehensive operational principle analysis and performance analysis are provided, and a 48 to 28−90 V/100-W prototype is built to verify the analysis.