The photochemical kinetics of phenanthrenequinone(PQ)doped poly(methyl methacrylate)photopolymer inholographic recording was studied theoretically and experimentally.The diffusion of PQ molecules during holographicrecording was negligible because of its small diffusion coefficient at room temperature. A photochemical reactionkinetics model of PQ/PMMA was established.The analytical expressions for the temporal variations of transmittanceand diffraction efficiency were derived.By fitting the experimental curves,some parameters related with the polymercomponents were obtained by the proposed model.which can be used to analyze the photochemical process and will behelpful to the optimization of material preparation.