The invention provides a successive approximation type analog-to-digital converter based on pre-emphasis, comprising: a capacitive digital-to-analog converter, one input end of which is connected witha sampling signal, the other input end of which is connected with a reference voltage, each capacitive switch in a capacitive array being controlled to be connected with a reference voltage of different potentials to output a conversion voltage according to a control signal; and a capacitive digital-to-analog converter; a comparator having one input terminal connected with a conversion voltage and the other input terminal connected with ground for comparing the sampled signal with the output comparison signal of the conversion voltage; a digital logic unit having an input end connected witha comparison signal and a clock signal, and an output end outputting the digital signal successively; and a pre-emphasis circuit having an input connected to a digital logic unit and an output connected to a capacitive analog-to-digital conversion unit for increasing a high-frequency component of the digital signal to output a pre-emphasized control signal. By adding a pre-emphasis circuit, the settling time of the capacitive digital-to-analog converter is shortened, and the conversion speed is improved with lower hardware consumption and power consumption without sacrificing linearity.