A theoretical model for CD-R dye coating on a substrate with spiral pre-groove is presented. A typical CD-R dye coating process consists of three stages: dispensing stage, spreading stage and vaporizing stage. Some assumptions and simplification for every stage are made and the second stage is mainly analyzed. The motion equation, boundary equations and continuity equation of flow for dye film are derived, taking into account topography on substrate and interface slip between liquid and substrate. Finally the governing equation is given.