Objective To investigate the effects of 18β-glycyrrhetinic acid (GA) on the expression of eotaxin 1 (CCL11), aquaporin protein 1 (AQP1) and eosinophil (EOS) in nasal mucosa of allergic rhinitis (AR) rats. Methods Seventy six Wistar rats were randomly divided into 4 groups,normal control (NC) group, AR model (AR) group, loratadine (LOA) group and 18β-GA group.All the mice in AR, LOA and 18β-GA groups were sensitized intraperitoneally with OVA and AL(OH)3 from day 1-14, then induced by intranasal administration with OVA from day 14-21, while the mice in NC group were sensitized with saline. The mice in both LOA and 18β-GA group were given LOA and 18β-GA once a day respectively from the 21 d, while the mice in AR and NC groups were administrated with saline.At the end of 1 week, 2 weeks and 3 weeks, the behavioral changes of mice were observed and recorded, the level of CCL11 mRNA was measured by RT-QPCR, and AQP1 expression was investiaged by SP staing.EOS in nasal mucosa was studied with the methods of HE staining. Results Compared with NC group , AR group showed typical AR symptoms. With the treatments,AR symptom scores and the expression levels of CCL11, AQP1 and EOS in nasal mucosa were improved significantly (PPP