An electrostatic charge-injection atomization method is shown to work, reliably for high-viscosity liquids of biological origin. An electrostatic charge-injection experiment has been built and calibrated against diesel fuel test data studied previously by other researchers using the same method of atomization. The atomizer electrical performance as a function of needle electrode distance front a grounded nozzle orifice and bulk-flow variations for raw soybean and corn oils is presented. The response of the total, spray, and leakage charge-injection currents of these oils with respect to the applied voltage is investigated and compared with U.S. diesel No. I fuel data. Because of the high viscosity of these vegetable oils, the jet breakup and spray mechanism show differences from those observed for lower viscosity mineral oils. An electrobending and spinning instability is observed that is similar to phenomena found in the flow of high-viscosity, poly,mer solutions.