The invention provides a method for supporting variable amplitude scanning of a bode diagram, and a digital oscilloscope. The method comprises the steps of: obtaining a variable amplitude configuration file set by a user on the digital oscilloscope; controlling a signal source to sequentially generate a segment of excitation signal corresponding to each group of configuration information accordingto various groups of configuration information of the variable amplitude configuration file, so as to input an excitation signal whose amplitude changes with frequency to to a circuit to be detected;obtaining an output signal generated by the circuit to be detected in response to the excitation signal, and calculating a measurement result of amplitude frequency response and/or the measurement result of phase frequency response according to the output signal, the excitation signal and the configuration information; and drawing the bode diagram according to the measurement result of amplitudefrequency response and the measurement result of phase frequency response. The invention not only provides a setting method of the variable amplitude configuration file, but also provides a scanning amplitude method for generating different frequency points, and the circuit to be detected is measured in a variable amplitude scanning manner, so that the measurement of special circuit by technicistsand the property analysis work of the bode diagram can be met.