Landscape architecture is an important component of the urban ecosystem and the only infrastructure with a carbon sink function in the city. It’s also the main component of achieving carbon neutrality in high-density areas. In view of global climate change, this study analyzed the carbon sink capacity of scientific and technological innovation and the development opportunities of disciplines from the perspective of policy guidance. It was proposed that the “double carbon” strategy is to change the runway rather than overtaking on the same track. It is a very challenging system project and needs to achieve qualitative change through a series of subversive changes, rather than quantitative change to qualitative change, and obtain the leading role in a new round of industrial revolution. In addition, this study combed the exploration and practice of the author’s scientific research team in recent years in three aspects: the construction of urban land space ecological network, the efficient landscaping construction of challenging urban sites, and the monitoring and evaluation of urban forest and green space carbon sequestration. The future work priorities under the support of cutting-edge subversive low-carbon technologies were summarized, including the preparation of action plans, the integrated restoration of urban land and ecological space, the construction of long-term carbon sink monitoring and measurement system, and the construction of management systems and mechanisms, with a view to accelerate the realization of carbon neutral goals through scientific and technological innovation in landscape architecture.