Abstract: The 15th Conference of the Parties (COP15) to the Convention on Biological Diversity (CBD) formally established the ambitious "30 by 30" target: conserving and effectively managing at least 30% of global terrestrial, inland water, coastal, and marine areas by 2030. As a CBD signatory and major maritime nation, China plays a pivotal role in global biodiversity conservation. Since the 1980s, China has incorporated key coastal and marine zones into its protected area system, establishing over 300 Marine Protected Areas (MPAs) covering more than 90, 000 km². However, critical gaps persist: current MPA coverage accounts for less than 4% of China′s jurisdictional waters, significantly below the global 30% target. Existing MPAs also face prominent challenges—including fragmented governance, inadequate management capacity, chronic underfunding, and unbalanced spatial development—that constrain their effectiveness in biodiversity conservation and degraded habitat restoration. A national-scale systematic assessment is therefore necessary to verify whether these issues are pervasive and identify dominant constraints.To address this knowledge gap, 40 MPAs were selected in China for an empirical study. We systematically identified the primary types of obstacles and their influencing factors in the ongoing development of MPAs, while conducting a comparative analysis of the target entities and coverage scopes of diverse response strategies. This study adopted an analytical framework encompassing a three-step process: "Barrier Identification-Systematic Assessment-Action Formulation." Relevant data were collected through field surveys and online questionnaires distributed to MPA managers and frontline staff. Statistical analysis of the survey responses was then employed to pinpoint the principal challenges across different MPA types and derive evidence-based recommendations.The findings reveal a nuanced landscape of constraints. A significant majority of respondents (65%) perceived resource-related barriers—including inadequate funding, insufficient staffing, and limited technical capacity—as more restrictive than governance or intent-based constraints. Further analysis distinguished between "weakly protected" areas (approximately 40% of the sample), where resource constraints were more pronounced, and "strongly protected" areas (the remaining 60%), which faced greater challenges in coordinating the interests and willingness of multiple stakeholders.Consequently, targeted interventions are required throughout the MPA lifecycle, from designation and establishment to long-term management. These interventions must not only enhance the capacity and professionalism of management authorities but also engage multiple stakeholders, including government policymakers, relevant institutions, and the general public. Aligned with the GBF′s emphasis on effective and equitable conservation, this study recommends prioritizing actions targeting leverage points in governance and resource allocation—domains where progress is more readily achievable—to improve the management efficacy of existing MPAs. Simultaneously, sustained efforts are needed to address deeper, more intractable challenges related to societal willingness and cognitive awareness, with the aim of securing broader understanding and support for marine conservation policies.