The previously reported O/O (Oil-in-oil) droplet generators are based on the usage of microfluidics and membrane emulsification techniques powered by external bulky syringe pumps. This configuration brings problems such as dead volume, air contamination, and difficult integration with other microfluidic components. The paper proposes an O/O droplet generator on a chip based on the integration of the MEMS (Micro Electro Mechanical Systems) technique and an electro-hydrodynamic method. In the generator, two ECF micropumps are used to pump the continuous and dispersed phase liquids, separately. By integrating our ECF micropumps, the droplet-generator-on-a-chip is easily fabricated, mainly using photolithography-based molding and electroforming. Among over 50 types of ECFs, we select HFE-7200 as a dispersed fluid and dibutyl decanedioate (DBD) with its surfactant of Span 80 at a concentration of 3% as a continuous fluid. We investigate the independent flow rates of two ECF micropumps, confirm the flow pattern diagrams of two-phase fluids, and examine the generated droplet diameter, the production rate, and the polydispersity index of O/O droplets. The results demonstrate that our device can generate O/O droplets with a low polydispersity index simply by adjusting the voltages applied to the ECF micropumps.