Objective To discuss the mechanism of action of bDNF on the intelligence of aged mice. Methods 90 Kunming mice over 55 weeks old were selected and randomly divided into groups. To observe the expression of choline acetyltransterase (ChAT-IR) and in the labyrinth experiment of each group before and after administration with integral experimental technique and immunohistochemistry. Results Significant changes of ChAT-IR AchE and labyrinthian experiment occurred (P<0.05) in the cytidine diphosphocholine group. Exogenous bDNF treatment group changed more significantly compared to CHAT AchE and labyrinth experiment (P<0.01). Conclusion bDNF can improve the intelligence in aged mice.