Embodiments of the present invention relate to the technical field of oscilloscopes and disclose a method and an apparatus for processing an oscilloscope signal and an oscilloscope. The method for processing the oscilloscope signal includes: obtaining a voltage signal; determining high and low level signals in the voltage signal according to a reference voltage; determining a valid digital signal from the high and low level signals; and displaying a waveform image of the digital signal. According to the embodiments of the present invention, the voltage signal may be converted into the digital signal without digital processing on the voltage signal via a hardware device such as an analog converter, thereby reducing costs of the oscilloscope and facilitating user operation and carrying.