Abstract: The ecological conservation redline is the bottom line and lifeline for safeguarding national ecological security. Assessing its long-term protection effectiveness lays the foundation for verifying whether the policies are effective and optimizing management strategies. Based on Xi'an City's ecological conservation redline data in 2022-2024, we applied the indicator system of the Technical Specification for Supervision of Ecological Conservation Redline—Protection Effectiveness Evaluation (on trial) (HJ 1143-2020), combined with remote sensing and GIS, to conduct a continuous dynamic assessment and calculate the values of indicators including protected area, land use type, ecological function and management capacity. The results showed that the comprehensive assessment results of ecological protection effectiveness were rated as "slightly improved" in both 2023 and 2024, indicating stable protection status and continuous improvement. During the assessment period, the redline area did not decrease; the proportion of natural ecological land and the vegetation cover index remained high; ecological restoration tasks were fully completed; no major ecological damage or environmental pollution incidents occurred; the air quality compliance rate and information disclosure rate increased significantly, and public satisfaction was high. The "annual rolling comparison" framework based on three consecutive years of data effectively identified temporal differences between management-response indicators and ecological-response indicators. The management capacity index was most sensitive to policy interventions and was the primary contributor to the improvement of protection effectiveness in the short-term assessment, whereas the ecological function index showed no significant change due to its high baseline value and lagged response. Furthermore, the current HJ 1143-2020 standard has limitations when applied to the complex inland ecosystems of Northwest China, including masking of spatial heterogeneity, incomplete characterization of ecological functions, and temporal response lags, necessitating localized adaptation. Annual dynamic assessment facilitates in-depth quantitative research on the indicator system. Integrating the results into government performance appraisals is recommended to inform precise regulation.