Cities concentrate almost 60% of the world’s population. Worldwide, urban populations are highly vulnerable to climate change. Urban green spaces and related ecosystem services help increase inhabitants’ quality of life and well-being and mitigate the impacts of climate change. Otherwise, in terms of urban planning, green spaces can raise a dilemma by reducing the space available for vehicle traffic and parking. In this paper, we focus on green spaces around the tram network in the Lyon metropolitan area, France, to assess the social demand for the greening of the urban transport infrastructure, using a Discrete Choice Experiment (DCE). The survey was conducted in 2022 with 500 inhabitants. Our results show that respondents are in favor of urban greening due to its capacity to reduce air temperature and increase biodiversity. However, they are, on average, against a high reduction of the available space for traffic and parking, as a result of urban greening development. Outcomes also demonstrate a high heterogeneity in inhabitants’ preferences partly driven by their sensitivity and commitment to the environment.