Various molecular weights of acid-labile polymers of tetrahydropyranyl methacrylate/3(4)-methylstyrene were evaluated as visible light sensitive positive-type photoresists for their application on rainbow holograms. The experimental results show that diffraction efficiency, S/N ratio and contrast of a reconstructed image from a rainbow hologram were influenced by the average molecular weight (Mn); the copolymer with Mn = 5 − 8 × 10⁴ gave better results and with a minimum exposure energy of 3.2 mJ/cm² using 488 nm laser light. It is possible to be applied to the production of the stamper for embossed holograms by means of using this copolymer.