We developed a Mach-Zhender (MZ) LiNbO 3 optical modulator, which has a half-wavelength voltage V π of 1.8 V, for millimeter-wave generation with a low drive voltage and a low input frequency. The MZ modulator can generate every other order of double-sidebands (DSBs) and maximize a desired DSB by controlling the drive voltage and the dc bias. In this study, we demonstrate 76 GHz millimeter-wave generation using 2 nd -order DSB at a drive voltage of 7 V p-p (3.1 V π ) and an input signal frequency of 19 GHz. Moreover, we present 4×f m generation without any filters using a bandwidth limitation of a PD module.