A modified activation process was developed for electroless Ni-P coating preparation of conductive mica powder. The electroless Ni-P coating process was modified by replacing the conventional sensitization and activation steps only using activation step with a Pd(II)-APTHS activator, which is a complex of Pd(II) ion with a derivate gamma-aminopropyttrihydroxysilane (APTHS) from the hydrolysis of gamma-aminopropyltriethoxysilane (APTES). The activated reaction progress and resulted Ni-P coating were characterized by XPS, SEM/EDX and TEM. Electroless nickel deposition was successfully initiated by this activation process. This activation process is very simple, and the obtained Ni-P deposits have the advantages of uniformity, continuity and densification. The average specific resistivity for the Ni-P coated mica powder was 4.85 x 10(-2) ohm cm. (c) 2006 Elsevier B.V. All rights reserved.