Biodiversity in the city plays a very important role in the balance of our planet. The presence of natural elements improves the ecological, social, environmental and aesthetic quality of the urban environment. The presence of biodiversity in the urban landscape can be promoted through various structures such as ecological corridors, wildlife crossings, green roofs and vines. The objective of the qualitative case study was to identify the ecological, technical and environmental factors that influence the restoration of biodiversity in the city. Four biodiversity restoration projects were studied in the Montreal and Quebec areas. Analysis of interviews with project stakeholders enabled the identification of different categories of facilitating factors including social, political, technical and ecological factors. According to the respondents, social factors are the main factors that facilitate the success of these projects. These factors include citizens’ acceptance and membership ; education and awareness ; residents’ participation ; choice of the location of the restoration sites ; involvement of NGOs and media coverage. Social acceptance of the biodiversity restoration strategies implemented emerges as the most important factor. Therefore, the success of an urban biodiversity restoration project depends largely on citizens’ support.