This paper focuses on lowering the half-wave voltage of lithium niobate (LN) electro-optic modulator. The principle of realizing the low half-wave voltage by the reflection structure is investigated. A reflection type electro-optic modulator is proposed and fabricated with x-cut LN crystal through the annealed proton-exchanged process. Preliminary results prove that the proposed reflection type LN electro-optic modulator can lower the half-wave voltage without increasing the length of device.