The purpose of this study was to determine the efficacy of rate of perceived exertion (RPE) to monitor exercise intensity in older adults. Middle-aged (46.9 ± 7.0 years, n = 24) and older women (75.5 ± 3.8 years, n = 29) performed a graded maximal exercise test on a cycle ergometer while RPE, oxygen uptake, heart rate, and blood lactate levels were measured. The Pearson’s product-moment correlation coefficient between RPE and oxygen uptake for each stage of the graded exercise test was calculated for each participant. The mean coefficient for the older group (r = .954) was similar to that of middle-aged group (r = .963). The autocorrelation coefficient was much lower (r = .411) in the older group than in the middle-aged group (r = .871). Variability in RPE through the graded exercise test was similar between the two groups. In conclusion, RPE was strongly associated with oxygen uptake in the older group. These results indicate that RPE is effective in monitoring exercise intensity in older adults.