Black carbon (BC) aerosols significantly impact the global climate and have emerged as a key research focus in atmospheric and environmental sciences. A core-shell model of BC aerosols has been developed, featuring BC as the core and sulfate, nitrate, and organic carbon as the shells. The discrete dipole approximation (DDA) method has been employed to explore how different mixing shapes and materials influence the optical properties of BC aerosols. Results indicate that smaller particles exhibit much higher extinction and scattering efficiencies than larger ones. Ellipsoidal particles demonstrate approximately 20%~30% higher extinction efficiency and 15%~25% higher scattering efficiency compared to spherical particles. Among the core-shell configurations, nitrate-coated ellipsoids have shown the most prominent absorption performance, with an absorption efficiency factor 40%~70% higher than that of sulfate- and organic-coated ellipsoids. Organic-coated ellipsoids have displayed a significant increase in the asymmetry factor, reaching around 0.8, which is 5%~15% higher than other mixtures. Regarding size distribution, sulfate particles have been found to form smaller sizes, whereas organic particles have exhibited a more uniform and slightly larger size distribution. An increase in BC radius has been shown to substantially alter the optical properties of the particles. The extinction efficiency factor has increased with the BC radius. The absorption efficiency factor has been enhanced, while the scattering efficiency factor has decreased. These findings have provided essential parameters for more accurately simulating the radiative effects of aerosols.