The development of disruptive technologies is a crucial pathway for China to achieve high-level self-reliance and strength in science and technology, as well as to develop new forms of productivity. Effective policy support is indispensable in this process. Systematic analysis and dynamic tracking of supportive policies for disruptive technologies can help identify good practices in policy support, which is essential for forward-looking planning of disruptive technologies. Taking the practice of policy protection for new energy vehicles as an example, this study introduces the theory of strategic niche management, constructs an analytical framework for policy protection space, and conducts a deep longitudinal analysis of the policy protection space for NEVs from 2001 to 2023 to explore the internal mechanism of its dynamic evolution, providing a new perspective for gaining insights into the dynamic mechanism of disruptive technology policy support. Based on these findings, the study proposes policy implications for establishing a supportive mechanism for disruptive technology policies, offering valuable references for long-term policy planning and scientific support of disruptive technologies.