Abstract: The multi-conductor transmission line(MTL) model used for analyzing taper winding in air-cored pulse transformer was build by multi-conductor transmission line theory. The reasoning formula of distributed parameter in its equivalent circuit were deduced, and then they were calculated by finite element method. Experiment was carried out to study the impulse voltage distribution on taper winding,such as turn-to-ground voltage and turn-to-turn voltage, the results were agreeable to that of calculation. Research indicates that distributed parameter on taper winding led to voltage oscillation during rising edge, which may create excessive voltage gradient in head of winding, the validity of MTL model is also proved.