The series resonant converter has attracted more and more attentions because of its resonant characteristic. However, the gain of series resonant converter is less than 1, which is not applicable for wide input voltage. In this paper, an innovative DC/DC converter integrated Buck-Boost and series resonant converter (IBBSRC) was put forward. The IBBSRC integrates intermediate leg of Buck-Boost converter and SRC to diminish amount of switches and switching losses. Besides, with the modulation strategy of two-edge-modulation + single-phase-shift ($\text{TEM}+\text{SPS}$), constant output voltage and zero voltage switching of switches are realized. Six operation modes for above resonant frequency operation were analyzed in detail. The parameter design and zero voltage switching of the converter were studied. Simulation results with an IBBSRC model were indicated to support the vlegality and viability of the propounded circuit topology.