A high speed, high repetition rate, bipolar solid-state high voltage modulator is under development at Brookhaven National Laboratory for muon electron conversion (MECO) experiment. The modulator will be used to drive a RF kicker consisting of a pair of parallel deflecting plates. The principle design is based on the inductive-adder topology. This system requires a fast pulse rise and fall time of approximately 20 ns, a pulse width of 100ns, a pulse repetition rate of 300 kHz, and a 60 kHz sinewave amplitude modulation. Fast high voltage MOSFETs are used as main switching devices. Different magnetic materials are being investigated for the adder core magnets. The main circuit design, critical subsystems, and major technical issues will be discussed. The circuit simulation, component selection and evaluation, and preliminary test results will be presented