Objectives: To evaluate the alterations in the anterior segment parameters, retinal nerve fber layer, and pupillary functions in smokers. Materials and Methods: In this case-control study, 45 eyes of 45 smokers and 45 eyes of 45 non-smoker control subjects were evaluated. All patients underwent measurement of anterior segment parameters with optical low coherence refectometry (OLCR), mesopic and photopic pupillary diameter with an aberrometer device, retinal nerve fber layer thickness with optical coherence tomography, and dry-eye assessment with Schirmer's test. The results were compared with independent t-test by SPSS 16.0 Inc., and a p-value lower than 0.05 was determined as signifcant. Results: There was a signifcant difference between both groups in terms of mesopic pupil diameters that were measured with both OLCR and aberrometer device (p=0.03 and 0.02, respectively). Schirmer scores were also signifcantly decreased in smokers (p=0.001). The other measured parameters demonstrated no difference between smokers and non-smokers (p>0.05 for all). Conclusion: Smoking may affect pupillary functions, especially the mesopic pupillary diameter, and may cause a defciency in pupil response under dark circumstances.