Objective：To detect expression of esopageal cancer related gene 4（ECRG4） in choroid plexus epithelial cells of purified rat in vitro. Methods：Primary and passage choroid plexus epithelial cells were obtained from 1 d newborn Sprague-Dawley rats. Expres－sion of ECRG4 was measured by qRT-PCR and Western blot. Secretion of ECRG4 was detected by ELISA. Cells were divided into primary cells（A），passage 1 cells（B） and passage 2 cells（C） groups. Cells which using MnCl2 were divided into intervening primary cells（D） groups. Results：①Expression of ECRG4 mRNA was higher in group B than in groups A and C with statistical differences（P=0.000）. There was no statistical difference in expression of ECRG4 mRNA between group A and group C（P=0.127）. Expression of ECRG4 mRNA was significantly reduced in group D than in group A（P=0.001）. ②ECRG4 protein expression was significantly higher in group B than in group A and group C. ECRG4 protein expression was significantly higher in group C than in group A（P=0.000）. ECRG4 protein expression was significantly higher in group A than in group D（P=0.000）. ③Secretion of ECRG4 detected by ELISA was significantly higher in group B than in group A and group C. Secretion of ECRG4 was significantly higher in group A than in group C（P=0.000）. There was no statistically significant difference between group A and group B（P=0.131）. Conclusions：ECRG4 might participate in the responding of choroid plexus epithelial cells to injury and influence bionomics of choroid plexus epithelial cells. The work on ECRG4 expression in choroid plexus epithelial cells can establish theoretical and experimental basement for clarifying the function of choroid plexus epithelial cell in nerve re－generation promoting.