Ecological restoration is suggested as a tool to mitigate environmental problems caused by urbanization, but its utility may be hampered by conflict between ecological design and neighbouring communities’ needs. We explore this issue by comparing vegetation diversity and structure in a 21-year-old urban reforestation project in Rio de Janeiro city, Brazil, with a nearby reference forest, and we assessed popular perceptions about the project. Overall, density and basal area of canopy trees in the restoration plantation reached 73% and 46%, respectively, of the values found in the reference forest, but ground cover by exotic grasses was substantially higher in the planted forest. Rarefied species richness was similarly high in the plantation forest (59 species) and in the remnant forest (69 species), but species composition was markedly different. The human legacy on restoration diminished with time, reflected in the higher proportion of species and individuals of late-successional, native and not-planted species in the seedling community of the plantation forest. While community perceptions of reforestation were positive and both use and non-use values were reported, interviewees reported little involvement in the development of the project, which could have contributed to synergies between ecological and social outcomes.