Abstract: In order to reveal the photosynthetic physiological characteristics of Carallia brachiata, C.brachiata seedlings were selected as the research object. The photosynthetic-light response curves was measured by Li-6400, and photosynthetic-optical response models suitable for C.brachiata seedlings were screened from the commonly used 6 photosynthetic curve fitting models. The results showed that the photosynthetic-optical response curve fitted by the right-angle hyperbola correction model was the best, and had a photo-inhibition phenomenon in accordance with the plant growth law. The P_max, I_sat, I_c, R_d were the closest to the measured values in the modified rectangular hyperbola model. The correlation coefficient R² was 0.998, which was the largest among the 6 models. The MAE and MSE were the smallest and the model had higher fitting accuracy. Therefore, the hyperbola correction model was the best fitting model for the photosynthesis-photoresponse curve of C.brachiata.