In this study，the efficiency of an energy conversion model for the piezoelectric bimorph cantilever beam generator（PMCBG）was established. The influence of the structural parameters and material properties of the PMCBG on the energy conversion efficiency was studied through numerical simulations and experimental testing. The research results show that the thickness ratio（TR）and Young’s modulus ratio（YMR）parameters affect the energy conversion efficiency of the PMCBG. Optimal TRs exist for the PMCBG to obtain maximal energy conversion efficiency in different metal-plate materials. When copper，aluminum，and molybdenum plates were used for the substrate，the PBCBG achieved optimal TRs of 0.3，0.1，and 0.2，respectively. With the same thickness ratio（0.3）and external excitation conditions，the energy conversion efficiency of the PMCBG using a molybdenum substrate was higher than that using copper or aluminum. When the YMR increased，the energy conversion efficiency of the PMCBG decreased but did not change significantly.