抗磷脂综合征（英语：Antiphospholipid syndrome，APS或APLS）是由于人体免疫系统对细胞膜成分磷脂发生异常自身免疫，产生抗体所引起的一组征候群。主要症状有动脉或者静脉血管栓塞、血小板减少以及与怀孕相关的胎死腹中、早产和自发性流产等，同时伴有抗心磷脂或者狼疮抗凝物实验持续阳性。

患者体内免疫功能失调会产生多种自身抗体。这些抗体引起血小板减少，同时破坏血管内皮细胞的完整性，导致血栓形成。怀孕妇女由于胎盘动静脉发生血栓，从而使得胎盘供血受阻，导致流产。

Antiphospholipid syndrome or antiphospholipid antibody syndrome (APS or APLS), or often also Hughes syndrome, is an autoimmune, hypercoagulable state caused by antiphospholipid antibodies. APS provokes blood clots (thrombosis) in both arteries and veins as well as pregnancy-related complications such as miscarriage, stillbirth, preterm delivery, and severe preeclampsia.