Abstract: Based on "resource-sink", physiology in cucumber and agricultural aerography theory, a dynamic simulation model for photosynthesis and dry matter accumulation in greenhouse cucumber was established. The model consists of leaf area dynamic formation, canopy photosynthesis, respiration and dry matter accumulation formation. The model parameters were determined by related literature and the experimental data. The model was examined by the data collected from the experiments with measuring dry matter accumulation of the different development stages in the whole development process in greenhouse cucumber. The results showed the relative prediction errors for dry matter accumulation in the different development stages between simulated values and measured values ranged within -3.0%～10.0%. This simulation model was of high accuracy, more mechanism and practicabitity.