The invention discloses a wide-spectrum and high-resolution optical coherence tomography imaging system. The power is reduced to be 20mW through adoption of a pohotonic crystal fiber supercontinuum source and an attenuation slice (AS). The whole system runs in a dark environment without other types of background light. Light emitted from the supercontinuum fiber light source is accessed to a free space optical coherence tomography imaging system, and a wideband achromatic lens is used for converging the light on a sample. A two-path balance detection method is employed to remove excess noise generated by the light source. A polarization beam splitter (PBS), a quarter-wave plate (QWP) and a half-wave plate (HWP) in an optical path help to optimize system output and improve sensitivity. All optical components selected by a time domain OCT system are suitable for a waveband range from 400nm to 1000nm. Complete interference fringe digital signals are obtained through an analog-digital converter with a sampling rate of 10Ms/s and a resolution rate of 16-bit.