Myopia is rapidly increasing in young populations and patients with glaucoma associated with myopia are reported to be young aged in East Asia. These young patients have a longer life expectancy, which increases their risk of end-of-life visual disabilities. There is a need to understand the clinical course of myopic glaucoma patients, which may be important for the care of these myopic populations. In this study, we evaluated the relationship between the age at presentation and the rate of glaucoma progression in the visual field (VF) according to the presence of myopia. The study was conducted as a prospective observational study including 179 patients with open-angle glaucoma who had undergone at least 5 VF examinations with a follow-up of at least 5 years. The progression rate of the mean deviation (MD) and the pattern standard deviation (PSD) are expressed as change in decibels (dB) per year. The slopes of the MD and PSD were calculated by linear regression analyses. Factors related to the slope of VF MD changes were analyzed with correlation and regression analyses. The slope of the linear fit line plotted against age at presentation and the rate of change in the VF MD was −0.026 (P < 0.001) in the myopic group and −0.008 (P = 0.167) in the nonmyopic group; the relationship was more prominent in the myopic group than the nonmyopic group. In the myopic group, age (β = −0.417; 95% confidence intervals (CI), −0.651 to −0.200; P = 0.050) and baseline untreated intraocular pressure (β = −0.179; 95% CI, −0.331 to −0.028; P = 0.022) were significantly related to the rate of change in the MD, which was only the presence of disc hemorrhage (β = −0.335; 95% CI, −0.568 to −0.018; P = 0.022) in the nonmyopic group. Age at presentation was significantly related to the rate of change in the VF in glaucomatous eyes with myopia compared to eyes without myopia. Older age was significantly related to the rate of change in the VF only in myopic glaucomatous eyes.