Objective: To determine the value of optic disc parameters and perimetric defects in the early diagnosis of patients with primary open-angle glaucoma (POAG). Methods: Optic disc parameters and perimetry were compared among patients in the early stage of POAG, patients with suspected POAG and healthy control subjects, using Heidelberg retina tomography (HRT-II), optical coherence tomography (OCT) and a Humphrey 750i automatic field analyser, in order to determine whether these parameters could be used for early POAG diagnosis. Results: A total of 55 participants were enrolled in the study. Significant differences in the optic disc parameter and perimetry values were observed between the three groups. HRT-II parameters showed good correlation with OCT parameters. The majority of the HRT-II and OCT parameters showed a good correlation with perimetry values. Conclusions: HRT-II and OCT optic disc parameters both reflect morphological changes of the optic disc. These current findings suggest that they can both detect glaucomatous optic neuropathy earlier than a white-on-white perimetry examination. In addition, OCT can detect optic disc parameter changes that cannot be detected by HRT-II.