The aim of the study was to determine which microperimetry and contrast sensitivity test parameters would prove the most valuable during diagnosing optic chiasm compression due to pituitary adenomas. A control group comprised healthy individuals (Group 1). Patients with pituitary macroadenoma were divided into two groups: Group 2 - absent optic chiasm compression; and Group 3 - present optic chiasm compression detected on contrastenhanced magnetic resonance imaging (MRI). Each group comprised 20 patients (40 eyes), i.e. a total of 60 patients (120 eyes) were examined. A complete ocular examination, intraocular pressure, microperimetry, contrast sensitivity test, kinetic Goldmann visual field, and static Octopus visual field test were performed. Group 1 and 2 variables showed no statistically significant differences with respect to the mean sensitivity (MS) and mean defect (MD) in microperimetry. After dividing the microperimetry area into quadrants, a difference was shown in the mean sensitivity of the lower-nasal quadrant (MS LN) and mean defect of the lower-nasal quadrant (MD LN) between those groups. Receiver operating characteristic (ROC) curves analysis revealed that the microperimetry parameter - MS LN as well as row D and E contrast sensitivity test could be highly specific in the assessment of early damage of the optic nerve in patients suffering from pituitary adenoma. Microperimetry and contrast sensitivity test are non-invasive diagnostic investigations adjunctive to MRI, which facilitate detection of early chiasmal compression caused by pituitary adenomas.