电子专业制造服务（EMS，Electronic Manufacturing Services），亦称ECM（Electronic Contract Manufacturing），中文又译为专业电子代工服务。相对于传统的ODM或OEM服务仅提供产品设计与代工生产，EMS厂商所提供的是知识与管理的服务，例如存货管理、后勤运输，甚至提供产品维修服务。

Electronic manufacturing services (EMS) is a term used for companies that test, manufacture, distribute, and provide return/repair services for electronic components and assemblies for original equipment manufacturers (OEMs). The concept is also referred to as electronic contract manufacturing (ECM).