[en] Objective: To explore the mechanism of injury in rat retina after the low dose laser exposure. Methods: Forty healthy male Wistar rats were randomly divided into the control group and 6 h, 12 h, 1 d, 3 d, 7 d, 14 d and 28 d seven time phase groups after the laser exposure. Their morphological and functional changes were observed with funduscope, histopathology, TdT-mediated dUTP nick end-labeling (TUNEL), immunohistochemistry, image analysis and electroretinograms. Results: There were diffuse histopathological changes in the whole retina and the changes in visual sensitive region below the optic disc were more obvious. Degenerative changes in different degrees occurred in the photoreceptor cells. TUNEL positive cells could be seen in all layers of retina after exposure, but mainly in the inner nuclear layer. The positive cells began to decrease on the 14th day. The reduction of b-wave amplitude of ERG indicated the decline of visual function. Conclusions: He-Ne laser (mean power density: 30 mW/cm², time: 15 min) can cause changes in the function and morphology of rat retina. The high expression of NMDAR may be one of the causes in retinal laser injury. (authors)