Silica nano-sol is the precursor (before gelation and drying) of silica gel and has much greater surface area than gel. In this study, a spherical commercial silica nano-sol in toluene with a dimension of less than 50 nm was successfully used to support two bridged metallocenes (dicholo - dimethyl silybis(indenyl) zirconium (IV) and dichloro - ethylenebis(indenyl) zirconium (IV),denoted by ZrSi and ZrEt, respectively). These sol-supported catalysts showed significantly better propylene polymerization activities than gel-supported catalyst reported earlier. The influences of solution co-catalyst ([Al4O3Me6](n,) n = 5-7, abbreviated as MAO) content and reaction time on polymerization were investigated. The increase of co-catalyst concentration increased activity, polymer length, and melting temperature. Polymer assemblies produced with ZrSi/Sol changed from diamond-shape to rod-like shape as time proceeded. Uniform dumbbell - shaped micro-sized polypropylene assemblies were obtained with catalyst ZrEt/Sol. The results were explained in terms of the penetration theory proposed before for multiphase mass transfer.