Abstract: Objective To investigate the level and significance of serum fibroblast growth factor 21(FGF-21) in patients with type 2 diabetic retinopathy. Methods A total of 120 healthy subjects in Hangzhou Xixi Hospital and Tongde Hospital of Zhejiang province from January 2016 to December 2018 were selected as group A, 120 cases of type 2 diabetic patients without retinopathy were selected as group B and 120 cases of type 2 diabetic retinopathy were selected as group C. Clinical and biochemical data were collected. The level of serum FGF-21 was measured by enzyme-linked immunosorbent assay. Results The FPG, FINS, HbA1 c, HOMA-IR, TG, TC, LDL-C and FGF-21 of group B and group C were higher than those of group A(all P<0.05), and HDL-C level was lower than that of group A(P<0.05).FGF-21 in group C [(3.47±0.51)μg/L] was higher than that in group B [(2.91±0.48)μg/L, P<0.05].There were no significant differences in glucose and lipid metabolism indexes between group B and group C(all P>0.05).There was positive correlation between serum FGF-21 level and FPG, FINS, HbA1 c, HOMA-IR, TC and LDL-C in patients with type 2 diabetic retinopathy(r=0.623, 0.652, 0.547, 0.633, 0.534, 0.242, all P<0.05).The results of multiple stepwise regression analysis showed that FPG(95% CI: 0.052-0.373), FINS(95% CI: 0.156-0.441) and TC(95% CI: 0.047-0.164) were independent influencing factors of serum FGF-21(all P<0.05). Conclusion Serum FGF-21 level is related to type 2 diabetic retinopathy, which is closely related to glucose and lipid metabolism, and may be involved in the development of type 2 diabetic retinopathy.