Abstract: Objective To study the expression of inflammatory factors in posterior segment of eyeball in rats exposed to short-term severe atmospheric pollution. Methods Thirty-six healthy female SD rats with SPF grade were randomly divided into control group,air pollution group and PM2.5 group,with 12 rats in each group.The control group did not receive any exposure treatment,two exposure groups received real-time collection of polluted air or polluted air in which the particulate matters larger than 2.5μm were filtered.The exposure time was 6 days.After death,pathological changes were observed on retinal HE staining sections.Expression of IL-1β,IL-5,IL-18,MCP-1 in the posterior segment of eyes were detected using the multifactor chip method.The expression of serum IL-1β was also detected. Results The median expressions of IL-1β in the posterior segment in control group and the other two exposed groups were 1.72 (1.56,2.24) pg/ml,2.98 (2.18,3.90) pg/ml,and 11.01 (7.12,26.06) pg/ml,respectively,with significant difference (P=0.001),and it was significantly higher in the two exposed groups than the control group (P<0.05,respectively).While,no significant difference was found in other factors between the three groups.The posterior segment of the exposed eyes had no significant difference with the control in pathological examination,and the serum IL-1β was not significantly different,too. Conclusion Short-term and severe air pollution with or without large particulate matters can promote the IL-1β expression in the posterior segment of eyes,whereas,the expression of IL-5,IL-18 and MCP-1 do not change significantly.This experiment suggests that short-term and severe air pollution may cause inflammation in the fundus.