Aim : To estimate and determine the prevalence of refractive errors in persons 40 years and older at the north suburbs of Athens-Greece. Method and material: The sample studied consisted of 1500 residents aged 40–77 living in the north suburbs of Athens-Greece. Refractive error was measured in a population-based sample composed of adults age 40 or older residing at the north suburbs of Athens. The participants were measured with an auto-refractometer (NIKON Speedy-1) and then the final prescription was tested with subjective refraction using a Snellen test chart in order to achieve 6/6 visual acuity. Aphakic eyes or eyes undergone cataract surgery, were excluded from analysis. Also eyes found to be < ± 0.50 Ds or having mixed astigmatism ± 0.25 Dc were considered to be emmetropic having 6/6 or 6/6 (-) visual acuity. Results: Prevalence rates were determined for myopia 42.67%, hypermetropia 14.40%, and emmetropia 42.33%. Myopia was categorized as low myopia (-0.50 D to -3.00 D) with 28.60% prevalence, as moderate myopia (-3.00 D to -6.00 D) with 13.47% prevalence and high myopia (>-6.00 D) with 1.20% prevalence. Hypermetropia categorized as low hypermetropia (+0.50 D to +2.00 D) with 9.60% prevalence, as moderate hypermetropia (+2.00 D to +4.00 D) with 3.27% prevalence and high hypermetropia (> +4.00 D) with 1.53%. Conclusions: Refractive errors affect approximately 57% of the population (40 years or older) at the north suburbs of Athens. Also the mean refractive error (Spherical Equivalent) is for the right eye – 0.6907 D (95% CI, - 0.7888 to – 0.5926 D) and for the left eye - 0.7458 D (95% CI, - 0.8464 to - 0.6453 D), respectively.