According to the spectral response curves and dark current of a near infrared two-dolor detector in two different operation wavebands, a signal acquisition system based on the near infrared two-color detector is designed. The system has many current-voltage conversion levels, voltage amplification levels and filter circuit bandwidth levels. It can amplify signals and control bandwidth quickly. Moreover, it provides zero analog signals for four amplify circuits via a Digital-to-Analog (D/A) convertor. This can effectively eliminate the noises caused by the stray light and the dark current of the detector itself. The system has the features of high speed, low noise and high resolution. By using this signal acquisition system, many parameters of the optical system, such as signal-to-noise ratio, dynamic range and minimum measurable power, can be improved.