OBJECTIVE To investigate the changes of cholinergic neurotrophic factors (CNTF) protein at different time points and the distribution of CNTF in rabbit retina after exposure to high power microwave (HPM), in order to determine the changes rule of CNTF protein. METHODS The rabbits were irradiated by HPM (peak power 90 W/cm(2)) for 15 min respectively, and then killed at 0, 3, 6, 12, 24 and 72 h after irradiation. The changes of CNTF protein were investigated by immunohistochemistry and semi-quantity analysis. RESULTS CNTF protein was distributed in full retinal layers, special in the cell membrane and cytoplasm. HPM irradiation could immediately down-regulated CNTF protein expression at 0 h, up-regulated and arrived at peak level at 6 h (P<0.05 vs 0 h group), and then kept control level. CONCLUSIONS HPM may cause acute retinal injure and change the expression of CNTF protein in rabbit retina. These effects show the time-dependent feature. These results suggest that CNTF activation plays a central role in the retinal injures induced by HPM, and supplies a therapy method by using foreign-aid CNTF to remedy the retinal injure induced by HPM.