The present disclosure discloses a method and a device of optimizing a SNR parameter. The method of optimizing the SNR parameter comprises: obtaining a capacitance signal of a touch screen without being touched and a capacitance signal of the touch screen being touched, respectively; filtering the capacitance signal of the touch screen without being touched to obtain a first filtered capacitance signal; filtering the capacitance signal of the touch screen being touched to obtain a second filtered capacitance signal; calculating an average value of the first filtered capacitance signal in a single period and an average value of the second filtered capacitance signal in the single period; compensating the average value of the first filtered capacitance signal or the average value of the second filtered capacitance signal; and determining the SNR parameter, according to a ratio of the compensated average value of the second filtered capacitance signal to the average value of the first filtered capacitance signal, or according to a ratio of the average value of the second filtered capacitance signal to the compensated average value of the first filtered capacitance signal. The method and the device of optimizing the SNR parameter are used for optimizing the SNR parameter applied to a touch screen, solving a problem of low accuracy of identifying a touch action by the touch screen.