Novel star-like hydrophobic (M) and hydrophilic (W) hybrid light-emitting dots were synthesized by grafting conjugated arms at eight vertexes of polyhedral oligomeric silsesquioxane (POSS) cage. The water-soluble cationic polymer W contains POSS as a core and two layers shell-an inner layer shell consists of the conjugated organic chain and a long chain of hydrophilic polymer as outer layer shell for solubilization in water. The 3D structure renders non-aggregation properties of W in solution as the wavelength for the absorption and luminescence spectra remains unchanged over different concentrations. The effects of ionic strength and pH on the properties of cationic polymer W were studied using UV, dynamic- and static-light scattering (DLS and SLS).