Laser absorption spectroscopy (LAS) technology is widely used in gas flow detection due to its advantages of high sensitivity, high precision, and non-contact measurement. In the application scenarios of combustion diagnosis, leakage detection, and localization, the demand for spatial distribution measurement has been presented. Laser absorption tomography (LAT) and laser absorption imaging (LAI) based on LAS technology can not only realize the two-/three-dimensional (2D/3D) imaging of flow field but also have good adaptability to the complex environment in practical engineering with high time resolution, which will still be the focus of research in related fields in the future. Here, the basic principles of LAS technology and the LAT and LAI methods were discussed. Moreover, the research and application states of the LAT and LAI methods at home and abroad in the past decade were mainly introduced, including linear and nonlinear measurements of LAT and 2D/3D imaging of LAI. Finally, the perspectives and trends of LAS-based 2D/3D imaging technology were reviewed.