BACKGROUND The aim of this study was to determine the 25-hydroxy vitamin D (25(OH)D) levels in age-related macular degeneration (AMD) patients. METHODS Age-related macular degeneration (AMD) patients were classified into four groups: early AMD (N = 10), intermediate AMD (N = 12), advanced atrophic AMD (N = 19) and advanced neovascular AMD (N = 52) after undergoing fundus photography. Serum 25(OH)D levels of all subjects were evaluated. From a random control group of 326 patients whose 25(OH)D levels had been measured, a group of 93 were selected to match the age range of the AMD group. We measured 25(OH)D levels during the same period to rule out seasonal variation. RESULTS A total of 93 AMD patients (36 males and 57 females) and 93 healthy individuals (39 males and 54 females) were enrolled in this study with the mean age of 78.96 ± 8.46 vs. 78.80 ± 8.35, respectively. The patients affected by AMD had statistically significant lower 25(OH)D levels (15 ± 10 ng/mL) than the healthy subjects control group (21 ± 14 ng/mL) (p = 0.004). However, the median 25(OH)D levels in early AMD, intermediate AMD, advanced atrophic AMD and advanced neovascular AMD (12.5 ± 7.3; 15 ± 11; 15 ± 8 and 17 ± 11.5, respectively) were not statistically significant (p = 0.442). CONCLUSIONS This study shows that patients affected by AMD had lower vitamin D levels compared to healthy subjects. Further research is necessary to investigate the possible association between 25(OH)D levels and AMD.