A substantial part of the population of Nagasaki, Japan, resides in houses built on slopes. Considering their reduced physical capacity, older people may suffer disproportionately from the disadvantage of living in such neighborhoods. This study examined two hypotheses: (1) buildings on a slope are less likely to have immediate access to a roadway, and (2) the percentages of older people/households are higher in such disadvantaged areas. Using a geospatial information system, the distance to the nearest roadway was calculated for individual buildings in the study area. Buildings that were located 10 m or more from a roadway were classified as buildings that do not have immediate access (“off-road”). For each 250×250-m spatial cell, the average slope angle of the land and indicators of aging were obtained. Pearsonʼs chi-square test was used to test hypothesis (1) and two-way ANOVA was used to test hypothesis (2). The chi-square test indicated that the percentage of offroad buildings was significantly higher in cells with a higher average slope angle (p<0.001). The two-way ANOVA showed that the indicators of aging were significantly associated with the average-cell-angle category and percentage of off-road buildings in cells, indicating that the percentages of older people/households in such disadvantaged areas are higher. The results indicate that older population suffers disproportionately from residing in environmentally disadvantaged neighborhoods in Nagasaki, implying an urgent need to redesign residential areas such that they are fairer to older population.