Abstract: Reactive P(St-BA-VBT)/dye composite nanospheres were prepared by dyeing poly(styrene(St)-butyl acrylate(BA)-vinylbenzyl trimethylammonium chloride(VBT)) nanospheres with reactive red 195. The nanoparticles were characterized by Scanning Electron Microscopy (SEM), nano-particle size and Zeta potential analyzer. The effects of dye content, dyeing temperature, dyeing time, bath pH on the adsoption quantities of dyes on the nanospheres were investigated. Results showed that P(St-BA-VBT)/dye composite nanospheres had uniform particle size and smooth surface. The diameter increased by 12.8 nm compared with the uncolored nanospheres and Zeta potential changed from 56.7 mV to -38.6 mV. Increasing dye dosage, dyeing temperature, dyeing time and decreasing bath pH, the adsorption quantities of dyes on the nanospheres increased. When the mass ratio of dye dosage to nanosphere was 5.25%, dyeing temperature was 65 °C and dyeing time was 90 min, the adsorption quantities of dyes on the nanospheres reached saturation.