The invention provides a direct-boost variable-excitation switched reluctance generator current conversion system comprising six switching tubes, three-phase windings, eight capacitors, six diodes, four inductors and a DC buck converter. The first switching tube, the second switching tube, the third switching tube and the fourth switching tube control the excitation and power generation work of each phase winding of the switched reluctance generator to raise the voltage output directly through the least switching tubes. The fifth switching tube and the sixth switching tube regulate and controlthe magnitude of the excitation voltage. The strengthening of excitation is considered, the problems of direct voltage boost and wide range change of excitation voltage under the condition of minimumswitching tubes and low switching stress and low loss and isolation, decoupling and voltage reduction can be solved and the occasions of higher power grade can be met. The whole system has high utilization rate, high efficiency and low cost and is suitable for application in the field of medium and high speed switched reluctance generator systems driven by various kinds of power.