A novel copper (Cu) nanoparticle carrier was fabricated using kapok natural microtubes as a substrate. Cu nanoparticles were grown on a thin polymer film on the surface of the kapok fibers. The polymer film was deposited on the surface of the microtube using a surfactant-assisted polymerization of acrylonitrile monomers. Cetyltrimethyl ammonium bromide (CTAB) was used surfactant. The contact angle decreased from 120.5 to 0 after polyacrylonitrile coating (PAN), which suggests improved hydrophilicity of the kapok fibers. Addition of 1.5 mL acrylonitrile and 0.020 - 0.035 g CTAB yielded evenly coated kapok fibers. Cu nanoparticles, with diameters of 82-186 nm, were formed on the surface of the composite by reducing 0.16 M copper sulphate (CuSO4) with hydrazine (N2H(4)) at 70 degrees C. EDX reveals that more Cu nanoparticles formed on the surface of PAN-kapok composites with 0.035g CTAB due to thicker PAN coating.