A conductive powder of coal gasification fine slag porous microbeads (CMs) coated with silver (Ag) nanoparticles was synthesized by a simplified electroless plating method. CMs were coated with uniform and dense Ag nanoparticles ([email protected]) to form a conductive structure consisting of internal conductive channels and a surface coating layer. The powder volume resistivity of [email protected] reached 1.47 Ω·cm. Subsequently, [email protected] were mixed with polypropylene (PP) to prepare an [email protected]@PP composite with a volume resistivity of 3.35 × 105 Ω·cm, a tensile strength of 26.06 MPa, and an elongation at break of 43.09%. Due to the high specific surface area (65.41 m2/g), small particle size (8.13 μm), and low density (1.51 g/cm3) of [email protected], the [email protected]@PP composite had better volume resistivity and mechanical properties than the PP composite filling with commercial silver-plated glass beads. The findings of this research could provide a theoretical foundation for future applications of [email protected]