LC parallel resonance circuit, the equivalent impedance is purely resistive and the value of the maximum, by using this feature, the resonant circuit in the integrated operational amplifier feedback resistor position, can be at the resonant frequency to achieve specific signal of a frequency selection amplifying. This design is mainly by the attenuation frequency selection network, a frequency selection amplifying module and automatic gain control module, the two integrated operational amplifier and frequency selection network combination, to achieve stable resonant amplification, amplification of up to 81dB, resonant frequency of 15MHz; by using 3.6V single power supply, the power consumption is only 320mW, observed in the spectrum analyzer waveform of high Q value, the smaller rectangle coefficient, frequency offset in 100KHz, 3dB bandwidth in the 300KHz, the whole system has stable output, no excitation signal output.