Purpose: To evaluate the effect of obstructive sleep apnea-hypopnea syndrome (OSAHS) on the meibomian glands, ocular surface, and tear parameters. Methods: The study included 59 individuals (32 subjects with OSAHS, 27 control subjects) who underwent polysomnography in the Chest Diseases Clinic. The right eyes of all individuals were evaluated in the Ophthalmology Clinic. The first noninvasive tear break-up time (f-NTBUT) and the average noninvasive tear break-up time were measured, and Schirmer test was applied. Meibography was taken (Sirius; CSO, Florence, Italy), and meiboscore was used for indexing meibography. Finally, a sample was taken for conjunctival impression cytology. Results: In the study and control groups, the median of f-NTBUT was 2.1 seconds [interquartile range (IQR); 1.5-5.0] and 5.7 seconds (IQR; 2.9-8.8) and the median of average noninvasive tear break-up time was 5.6 seconds (IQR; 3.6-9.5) and 7.2 seconds (IQR; 4.2-10.7), respectively (P= 0.007 andP= 0.487, respectively). The mean Schirmer value was 16.3 +/- 5.9 mm (range; 5-25) and 17.3 +/- 6.6 mm (range; 5-30) in the study and control groups (P= 0.604). In upper eyelid meibography, the median of loss in the meibomian glands was 20.10% (IQR; 11.60%-40.80%) in the study group and 14.70% (IQR; 10.40%-21.30%) in the control group (P= 0.043). In lower eyelid meibography, the median of loss in the meibomian glands was 19.00% (IQR; 13.60%-35.30%) in the study group and 12.40% (IQR; 9.10%-16.40%) in the control group (P= 0.002). The median of the Nelson grade in conjunctival impression cytology was 1 (IQR; 0-1) in the study group and 1 (IQR; 0-1) in the control group (P= 0.445). Conclusions: The loss in the meibomian glands together with the shortened f-NTBUT shows that there could be a predisposition in OSAHS for evaporative dry eye originating from meibomian gland damage.