A sampling method for anti-counterfeiting information of a cash note, comprising: step 1 of collecting voltage waveform data V int erference outputted by a sensor (32, 33) for obtaining interference signals and voltage waveform data V effective outputted by a sensor for obtaining effective signals, during a sampling interval of obtaining anti-counterfeiting information of cash notes by the sensor for obtaining effective signals during the sampling interval, wherein the voltage waveform data V int erference outputted by the sensor (32, 33) for obtaining interference signals and the voltage waveform data V effective outputted by the sensor for obtaining effective signals are obtained according to the following formulas: V int ⁢ erference = K 1 Sin ω 1 t + φ 1; V effective = K 2 Sin ω 2 t + φ 2; where: ω 1 = ω 2, which represent angular velocities corresponding to a frequency of an interference source; Ø 1 represents phase information of the interference signals, Ø 2 represents phase information of the effective signals, and Ø 1 = Ø 2; K 1 is signal amplitude of the interference signals, and K 2 is signal amplitude of the effective signals; step 2 of calculating a response ratio coefficient K of the sensor (32, 33) for obtaining interference signals and the sensor for obtaining effective signals with respect to electromagnetic interference signals according to the formula: K = V effective / V int ⁢ erference = K 2 / K 1; step 3 of sampling, by the sensor for obtaining effective signals, anti-counterfeiting information of a cash note, and outputting voltage waveform data V' effective corresponding to the anti-counterfeiting information during a time period of the cash note passing through the sensor for obtaining effective signals; step 4 of collecting voltage waveform data V ' int erference outputted by the sensor (32, 33) for obtaining interference signals during the time period of the cash note passing through the sensor for obtaining effective signals; step 5 of restoring voltage waveform data V sup erposition superposed with an electromagnetic interference signal and outputted from the sensor for obtaining effective signals according to the formula V sup erposition = K ∗ V ' int erference; and step 6 of performing common-mode signal elimination on the voltage waveform data corresponding to the anti-counterfeiting information according to the formula V anti-counterfeiting = V' effective - V sup erposition, to obtain voltage waveform data V anti-counterfeiting corresponding to the anti-counterfeiting information after performing the common-mode signal elimination. step 1 of collecting voltage waveform data V int erference outputted by a sensor (32, 33) for obtaining interference signals and voltage waveform data V effective outputted by a sensor for obtaining effective signals, during a sampling interval of obtaining anti-counterfeiting information of cash notes by the sensor for obtaining effective signals during the sampling interval, wherein the voltage waveform data V int erference outputted by the sensor (32, 33) for obtaining interference signals and the voltage waveform data V effective outputted by the sensor for obtaining effective signals are obtained according to the following formulas: V int ⁢ erference = K 1 Sin ω 1 t + φ 1; V effective = K 2 Sin ω 2 t + φ 2; where: ω 1 = ω 2, which represent angular velocities corresponding to a frequency of an interference source; Ø 1 represents phase information of the interference signals, Ø 2 represents phase information of the effective signals, and Ø 1 = Ø 2; K 1 is signal amplitude of the interference signals, and K 2 is signal amplitude of the effective signals; step 2 of calculating a response ratio coefficient K of the sensor (32, 33) for obtaining interference signals and the sensor for obtaining effective signals with respect to electromagnetic interference signals according to the formula: K = V effective / V int ⁢ erference = K 2 / K 1; step 3 of sampling, by the sensor for obtaining effective signals, anti-counterfeiting information of a cash note, and outputting voltage waveform data V' effective corresponding to the anti-counterfeiting information during a time period of the cash note passing through the sensor for obtaining effective signals; step 4 of collecting voltage waveform data V ' int erference outputted by the sensor (32, 33) for obtaining interference signals during the time period of the cash note passing through the sensor for obtaining effective signals; step 5 of restoring voltage waveform data V sup erposition superposed with an electromagnetic interference signal and outputted from the sensor for obtaining effective signals according to the formula V sup erposition = K ∗ V ' int erference; and step 6 of performing common-mode signal elimination on the voltage waveform data corresponding to the anti-counterfeiting information according to the formula V anti-counterfeiting = V' effective - V sup erposition, to obtain voltage waveform data V anti-counterfeiting corresponding to the anti-counterfeiting information after performing the common-mode signal elimination.