To address the challenges in the precise identification and quantitative concentration retrieval of atmospheric aerosols, this study proposes an aerosol identification method based on Mueller matrix pattern analysis, focusing on polarization characteristics. Using optical depth as a concentration-equivalent parameter, the evolution of polarization scattering and depolarization characteristics for two typical particle types—smoke (irregular, strongly absorbing) and water mist (spherical, weakly absorbing)—is systematically investigated through combined simulation and experiment at optical depths of 0.77, 2.27, and 4. The results indicate that optical depth is the key parameter governing the macroscopic evolution of polarization and depolarization properties. As it increases from 0.77 to 4.00, the total scattering intensity (M11) and circular polarization preservation capability (M44) increase significantly, with the scattered depolarization intensity rising by more than 75%. The microphysical properties of the particles are the fundamental factor determining differences in their polarization response. At the same optical depth, the M44 value for water mist particles is approximately 76% higher than that for smoke particles, and their scattering images exhibit a unique “fragmented” texture due to discrete droplet distribution. Furthermore, the angular distribution features of key matrix elements (e.g., the peaks of M11 and M44 at 180°) demonstrate good robustness and can serve as effective indicators for identification. Experimental validation shows that the relative error between measured and simulated key parameters is within 6%, confirming the reliability of the method. This study demonstrates that Mueller matrix analysis can simultaneously and sensitively extract polarization information modulated by both particle microstructure and medium concentration, providing a new and effective approach for the high-precision identification and retrieval of atmospheric aerosols based on polarimetric remote sensing.