2008年汶川地震、2010年玉树地震、2014年鲁甸地震等大量震例研究表明，严重的地震灾害损失和人员伤亡主要源于发震断层的同震地表破裂、近断层的强地面运动和地基失效引起的建（构）筑物倒塌。因此，避让活动断层是有效减轻可能遭遇的地震灾害损失的一项重要措施。但如何避让活动断层和避让多少距离能够保证地面建（构）筑物不受活动断层同震错动引起的直接毁坏，一直是国内外学者争论的焦点科学问题。1）首先基于历史地震地表破裂资料，定量分析了活动断层同震地表破裂的局部化特征、同震地表破裂与建（构）筑物的破坏关系，得出了地震地表破裂带及其直接严重地震灾害带宽度的平均统计值约为30m的认识。2）通过1999年集集地震、2008年汶川地震等地表破裂带宽度资料和地震灾害空间分布关系的分析，指出了倾滑断层具有明显的上盘效应，断层上、下盘地表破裂带或严重地震灾害带宽度之比为2︰1至3︰1。3）基于上述分析获得的最新认识，进一步讨论了避让对象、活动断层定位要求、不同类型活动断层最小避让距离、特殊建（构）筑物避让和“抗断”设计理念等问题。最后，呼吁立法机构加强活动断层避让和活动断层探测的立法工作，规范活动断层上及其邻近地段土地利用规划和基础设施建设过程中合理避让活动断层的行为，防患于未然，提高中国防震减灾的基础能力。

Living with disaster is an objective reality that human must face especially in China. A large number of earthquake case studies, such as the 2008 Wenchuan earthquake, 2010 Yushu earthquake, 2014 Ludian earthquake, have demonstrated that earthquake heavy damage and casualties stem from ground-faulting or rupturing along seismogenic active fault, near-fault high ground accelerations and building catastrophic structural failure. Accordingly, avoidance of active faults may be an important measure to effectively reduce earthquake hazard, which may encounter in the future, but how to avoid an active fault and how much a setback distance from the active fault is required to ensure that the ground faulting and rupturing has no any direct impact on buildings. This has been the focus of debate both for domestic and foreign scholars. This paper, first of all, introduces the definition of active fault. Then, quantitative analyses are done of the high localization of earthquake surface ruptures and relationship between the localized feature of the coseismic surface ruptures and building damages associated with the measured widths of the historical earthquake surface rupture zones, and an average sstatistic width is obtained to be 30m both for the earthquake surface rupture zones and heavy damage zones along the seismogenic fault. Besides, the widths of the surface rupture zones and spatial distribution of the building damages of the 1999 Chi-Chi earthquake and 2008 Wenchuan earthquake have also been analyzed to reveal a hanging-wall effect:Width of surface rupture zone or building damage zone on the hanging-wall is 2 or 3 times wider than that on its foot-wall for a dip-slip fault. Based on these latest knowledge learnt above, issues on avoidance object, minimum setback distance, location requirement of active fault for avoidance, and anti-faulting design for buildings in the surface rupture zone are further discussed. Finally, we call for national and local legislatures to accelerate the legislation for active fault survey and avoidance to normalize fault hazard zoning for general land-use planning and building construction. This preventive measure is significantly important to improve our capability of earthquake disaster reduction.