The purpose of the present investigation was to determine whether blue-on-yellow (B/Y) perimetry using a screening program can detect early glaucomatous change before it is evident with standard white-on-white (W/W) screening tests. The subjects included 25 normal, 20 ocular-hypertensive and 27 early glaucomatous eyes. From our results, even in normal subjects, B/Y perimetry alone demonstrated abnormal points in the nasal field in 10 eyes (40%). The Armaly central screening program was thought to be superior to the Armaly full-field program, because the former has less probabilities to detect a false-positive scotoma in the nasal field than the latter. In glaucomatous eyes, more abnormal points were detected by B/Y perimetry than by W/W perimetry. The screening program of B/Y perimetry is more advantageous than conventional tests in detecting early glaucomatous visual field defects.