The societal functions and values of trees planted in urban areas is conducted in Brazzaville, in the district No. 8 Madibou. The concept of resilient and ecological cities stipulates, a significant woody cover with carefully selected species and individuals ordered according to well-defined requirements, in the urban space. The study highlights the perception of ecosystem services and disservices by the residents and the daily coverage of their needs. A less sustained theme, the study is based on botanical inventory and ethnobotanical survey data. The floristic inventory conducted in 197 housing plots with at least two trees of dbh ≥ 10 cm, counted 1202 individuals corresponding to 49 species and 27 families, the distinctive ones being Arecaceae and Fabaceae. The fruit trees are privileged and the dominant ones in decreasing number of individuals are <i>Mangifera indica, Persea americana, Dacryodes edulis </i>and<i> Elaeis guineensis</i>. Ethnobotanical data, according to socio-professional and age classes, reveal 22 ecosystem services covering the three main categories of which regulatory services are highly valued. The average woman's perception of ecosystem services and disservices reaches 2/3 of citations per item. Notwithstanding the benefits rendered to populations, trees would affect social cohesion; without minimizing the disservices caused by their organs on roads, houses, physical communication infrastructures, goods and other properties. Since the added value is unequivocal, increasing forest cover would be the ideal solution for improving and maintaining the well-being of city dwellers, urban resilience and mitigating the effects of climate change, particularly urban heat islands. Urban arboriculture as a provider of ecosystem goods and services induces disservices while remaining a source of perpetuation of the Us and customs of the residents, via the virtues of biodiversity.