A digital multimeter includes a single chip processor, a sound chip connected to the single chip processor, a signal amplifying circuit, a speaker connected to the signal amplifying circuit, and a power source for providing electrical energy for the digital multimeter. The single chip processor collects high and low level signals, and converts the signals into codes which the sound chip can recognize, and transmits the codes to the sound chip. The sound chip converts the codes into audio signals and transmits the audio signals to the signal amplifying circuit. The signal amplifying circuit amplifies the audio signals and outputs the amplified audio signals to the speaker. The amplified audio signals reports the measurement values of the digital multimeter.