The invention discloses a signal filtering processing comparison system based on an analog-to-digital converter. The system comprises a signal source, voltage followers, a filter, signal conditioningcircuits, an AD converter and a PC. The voltage followers, the filter, the signal conditioning circuits, the AD converter and the PC are connected with the signal source. The filter comprises a passive low-pass filter and a multi-order active Bessel low-pass filter. The first voltage follower is directly connected with the first signal conditioning circuit without filtering processing. The secondvoltage follower passes the passive low-pass filter and then is connected with the second signal conditioning circuit. The third voltage follower passes the multi-order active Bessel low-pass filter and is connected with the third signal conditioning circuit. The three signal conditioning circuits are connected with the AD converter. Digital signals output by the AD converter are uploaded to the PC. According to the invention, the effects of processing the same simulation interference signal in different filtering ways can be compared and analyzed and effective measures, for coping with interference of a grounding net, for an electronic transformer acquisition unit are finally obtained.