AIM: To investigate the thickness of the retinal nerve fiber layer (RNFL), the ganglion cell layer (GCL), inner plexiform layer (IPL), and choroid thickness (CT) in patients with pituitary tumours, microadenoma and macroadenoma, using spectral optical coherence tomography (OCT). METHODS: Thirty six patients who had micro and macroadenoma, and 34 healthy participants (control group) were included in the study. Spectral OCT was used to measure the RNFL, GCL, IPL, and CT values for all patients. CT measurements were performed by the same author (A.S.K). Additionally, retinal nerve fiber length, which is a sublayer of ganglion cell complex (GCC), was also measured for each patient and after segmentation oF GCC. RESULTS: No difference was detected between group according to sociodemographic data. The mean age of patients and the control group was 34.31 ± 12.47 and 33.12 ± 11.75 years, respectively. In the patient group had RNFL thinning while there was a thickening of the choroid layer. When all pituitary tumours patients (without grouping) were compared with the control group and there were significant differences on all parameters: RNFL, GCL, IPL thickness, and CT (p<0.05), while there were no significant differences in RNFL and GCL measurements between microadenoma and macroadenoma (p>0.05). All patients were significantly different from one another with respect to CT (p<0.05). CONCLUSIONS: These findings suggest that neurodegeneration occurs in the course of pituitary tumours, and this degeneration may be presented by decreased GCL at early stages, and as the disease progresses it may also affect ather layers of GCC like RNFL and IPL. RNFL and GCL were significantly thinner in the all patients as compared with the control subjects. In pituitary tumours, both microadenoma and macroadenoma, when evaluating ophthalmological findings patients’ choroid thinning should be considered.