Objective To evaluate the efficacy of sevoflurane in preventing depression-like behavior in mice and the relationship with brain-derived neurotrophic factor (BDNF)/tyrosine kinase B (TrkB) signaling pathway.Methods Forty-four clean-grade male C57BL/6 mice,weighing 18-22 g,aged 8-10 weeks,were divided into 2 groups (n =22 each) using a random number table method:control group (group C) and sevoflurane group (group S).Mice in group C inhaled oxygen for 30 min,and mice in group S inhaled 2.5％ sevoflurane for 30 min.The forced swimming test and novelty-suppressed feeding test were performed after the mice were fully awake.The brains were immediately removed under anesthesia at the end of inhalation of oxygen or sevoflurane,and the prefrontal cortex and hippocampus were isolated for detection of the expression of BDNF,TrkB and phosphorylated TrkB (p-TrkB) by Western blot.Results Compared to group C,the immobility time and feeding latency were significantly shortened,the expression of p-TrkB in the prefrontal cortex and hippocampus was up-regulated (P＜0.05),and no significant change was found in the feeding consumption or expression of BDNF and TrkB in the prefrontal cortex and hippocampus in group S (P＞0.05).Conclusion Sevoflurane produces a preventive effect on depression-like behavior in mice,and the mechanism is related to increased phosphorylation of TrkB in BDNF/TrkB signaling pathway.