OBJECTIVE： To study inhibitory effects of propofol on PC12 cells injury induced by glutamic acid via mitogen-activated protein kinase/extra-cellular regulated kinase （MAPK/ERK） signal pathway. METHODS： PC12 cells were randomized into normal control group， model group （10 mmol/L glutamic acid）， propofol low-concentrations， medium-concentrations and high-concentrations groups （12.5， 25， 50 μmol/L+10 mmol/L glutamic acid）. The optical density of cells， cell apoptosis， the phosphorylation of ERK1/2 and the expression of c-fos， Bax， Bcl-2 were detected after treated with relevant medicine for 48 h. RESULTS： Compared with normal control group， optical density of cells， the phosphorylation of ERK1/2 and Bcl-2 decreased in model group （P＜0.01）； apoptotic rate， the expression of c-fos and Bax increased （P＜0.01）. Compared with model group， optical density of cells， the expression of Bcl-2 and the phosphorylation of ERK1/2 increased in propofol group （P＜0.01）； apoptosis rate， the expression of c-fos and Bax decreased （P＜0.05 or P＜0.01）. There were statistical significant between the different concentrations （P＜0.01）. CONCLUSIONS： Propofol can inhibit the apoptosis of PC12 cells induced by glutamic acid， which is associated with the up-regulation of ERK1/2 phosphorylation.