Abstract: Transmission lines are widely used in the fast signal transmission at short distances due to its low cost. But its bandwidth should be compensated for its narrowband. A compensation method based on filter is provided and the compensators of small size are designed and used in QG-Ⅰ accelerator. Experimental results show that the transmission bandwidth could reach 200 MHz and the amplitude of signal could be 1/3 of the original one after compensation. The comparison of original, uncompensated and compensated signals shows that signals’ aberrations can be well compensated with this method, which meets the demand of the high speed signal transmission in the QG-I accelerator. A software for compensator design has been developed for the automation of Pole-Zeros finding and element parameter