Organosilicon complexes were synthesized via a green chemical process using silica nanoparticles derived from rice husk (RH) biomass. By controlling the pre-treatment of RHs and pyrolysis conditions, silica samples with various surface areas and degrees of crystallinity were synthesized. Such silica can be converted to silicon complexes via a low temperature approach. The synthesized silicon complexes were characterized by ¹H, ¹³C, ²⁹Si nuclear magnetic resonance and elemental analysis. Overall, the biogenic silica nanoparticles with high surface area and low crystallinity exhibit high reactivity, comparable to commercial fumed silica. Considering their high reactivity and low cost, such biogenic silica nanoparticles from RHs are ideal starting materials to produce organosilicon compounds.