To analyse the expression of lncRNA-ANRIL and other related factors in different human body fluids, explore the clinical significance of ANRIL and validate whether ANRIL is interrelated with the renin-angiotensin system and NF-κB signalling pathway. Ninety-one patients were included in this cross-sectional study and were divided into the NDM group (20 patients), DM group (25 patients), NPDR group (21 patients) and PDR group (25 patients). Basic information and samples of serum, aqueous fluid and vitreous fluid were collected before vitrectomy or intravitreal injection. The transcription and levels of ANRIL and other related factors were detected by RT-PCR and ELISA. Statistical Package for Social Sciences software was used for statistical analysis. ANRIL expression varied among different groups and body fluids. There was no difference in ANRIL expression between the NDM and DM groups, but the level of ANRIL was significantly lower in the DM group than in the NPDR and PDR group. In vitreous fluid, ANRIL expression was positively correlated with Ang II, p65 and VEGF expression in the PDR group. The expression of ANRIL in serum was not significantly correlated with age or the random blood sugar but was positively correlated with diabetic duration and HbAc1 level. Levels of lncRNA-ANRIL are higher in DR patient and correlated with the progression of DR that may be used as an indicator to predict the development of DR. The activation of the RAS and the NF-κB pathway may be closely related to the upregulation of ANRIL. Clinical trial number ChiCTR1800017500. Registry Chinese Clinical Trial Registry.