In this paper, a CO₂ laser is used as the heating source to study the rapid pyrolysis process of solid fuel (coal and Eucalyptus) particles in an argon atmosphere. Laser-induced breakdown spectroscopy (LIBS) technology is applied to study the temporal and spatial distribution characteristics of pyrolysis products (including C, H, O, CN, and C₂). The experimental results show that the pyrolysis process of coal and Eucalyptus presents two stages, namely the dehydration and desorption stage and the macromolecular decomposition stage. In the dehydration and desorption stage, Eucalyptus thermally desorbed more carbon and nitrogen components than coal; in the macromolecular decomposition stage, the peak time of the precipitation of various elements in Eucalyptus is significantly later than that of coal. Besides, in the macromolecular decomposition stage, the proportion of H and O in the volatile components precipitated by Eucalyptus is larger, and the proportion of CN and C₂ in the volatile components precipitated by coal is larger. It can be seen from the ratio of residual energy and H spectral intensity value to C spectral intensity value that the change rule of the two presents a good consistency, which proves that the distribution of macromolecular components such as tar is closer to the fuel surface, and the concentration of small molecular gas components increases with height above the sample surface.