Objective To study the role of Homer1b/c in cell autophagy induced by glutamate excitotoxic injury and its mechanism. Methods Mouse hippocampal neuronal HT22 cells were treated with 500 μmol/L L-glutamate to establish cell injury model. The expression of Homer1b/c in HT22 cells was down-regulated by small interfering RNA (siRNA) lentivirus transfection. 10 μmol/L 1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid tetrakis (acetoxymethyl ester) (BAPTA-AM, a calcium ion chelating agent) and 10 mmol/L 4-phenylbutyric acid (4-PBA, an endoplasmic reticulum stress inhibitor) were used to inhibit intracellular calcium ion release and endoplasmic reticulum stress, respectively. Then, the expression levels of Homer1b/c, autophagy proteins (beclin-1 and microtubule-associated protein 1 light chain 3 [LC3]) and endoplasmic reticulum stress marker proteins (C/EBP homologous protein [CHOP] and glucose regulated protein 78 [GRP-78]) in cells were measured by Western blotting. Results Compared with the control group, the expression of beclin-1 and the ratio of LC3-Ⅱ/LC3-Ⅰ were significantly increased after the HT22 cells were treated with L-glutamate for 12 h (both P<0.05); down-regulation of Homer1b/c expression could reduce the expression of beclin-1 and the ratio of LC3-Ⅱ/LC3-Ⅰ (both P<0.05). Inhibition of intracellular calcium release and endoplasmic reticulum stress could reduce the beclin-1 expression and LC3-Ⅱ/LC3-Ⅰ ratio (both P<0.05). After down-regulation of Homer1b/c expression, inhibiting intracellular calcium release and endoplasmic reticulum stress failed to further reduce the beclin-1 expression and LC3-Ⅱ/LC3-Ⅰ ratio. Conclusion Homer1b/c can regulate cell autophagy induced by glutamate excitotoxic injury, and its regulatory effects may be related to the function of endoplasmic reticulum.