The invention relates to a microlens array and pulse laser based dispersion medium optical parameter field reconstruction device and method, and belongs to the field of infracted optical imaging. A technical method measuring optical field signals via a microlens array lacks at present. In the reconstruction device, a data processing system (7) is connected with a laser controller (1) and three microlens array light field cameras, the laser controller (1) is connected with a laser head (2), and a dispersion medium (3) is arranged at the center of an area enclosed by the laser head (3) and the three microlens array light field cameras. The reconstruction method comprises measuring emitting radiation in the medium boundary, calculating transmission of near-infrared pulse laser in the dispersion medium and reconstructing an optical parameter field. According to the invention, the optical parameter field of the dispersion medium is reconstructed, and new technical means is provided for near infrared optical imaging and infrared detection.