Abstract: Objective To observe the effect of anti-vascular endothelial growth factor(VEGF)in treating diabetic macular edema(DME)and its effects on serum nitric oxide synthase(NOS), VEGF, interleukin-6(IL-6)and hemodynamic parameters of nasal posterior ciliary artery. Methods A total of 98 patients(122 eyes)with DME treated with anti-VEGF were selected as research objects, and 56 patients(72 eyes)who were sensitive to treatment were included in the sensitive group, and 42 patients(50 eyes)who were insensitive to treatment were included in the control group. The macular fovea retinal thickness and hemodynamic parameters of nasal posterior ciliary artery, levels of NOS, VEGF and IL-6 were measured before and after treatment. Results The continuous interruption rate of extraretinal plexiform layer in the treatment sensitive group was 9.72%, which was significantly lower than 72.00% in the treatment insensitive group(P<0.05). The retinal thickness of macular fovea in the sensitive group after treatment was(301.12±67.28)μm, which was significantly lower than(410.11±52.21)μm in the control group(P<0.05). The peak systolic blood flow velocity(PSV)and end diastolic blood flow velocity(EDV)in the treatment sensitive group after treatment were significantly higher than those in the treatment insensitive group(P<0.05). After treatment, the NOS level in the sensitive group was significantly higher than that in the control group(P<0.05), while the levels of VEGF and IL-6 were significantly lower than those in the control group(P<0.05). Conclusion Anti-VEGF therapy has a certain effect in treating DME. Retinal thickness of macular fovea, hemodynamic parameters of nasal posterior ciliary artery, levels of serum NOS, VEGF and IL-6 are significantly better in sensitive patients than those without sensitivity.