Several polymeric auto dyes were synthesized by polymer reactions on polystyrene. As intermediates, polynitrostyrene and polyaminostyrene were prepared by nitration of polystyrene and following reduction respectively. The structures of these intermediates were investigated by elemental analysis and infrared spectroscopy, The polymeric auto dyes were prepared by diazotization and following coupling reaction on free amino group of polyaminostyrene. The polymeric dyes thus obtained were insoluble in water and general organic solvents. The colors of these dyes were determined by visible spectroscopy.