高效滤网（英语：High-Efficiency Particulate Air，即高效率空气微粒子过滤网，简称HEPA）是一种用于空气净化的器材。 符合HEPA标准的过滤器的用途很广泛，从医疗设备、汽车、飞机及家居均可应用。 截经过滤网的空气中所含有的微小尘埃。滤网的标准由美国能源部设置，对粒径在0.3μm的粒子， 过滤效果约为DOP 99.97%以上。通常使用的高效滤网可达到99.99%的拦截效率，也有更高或相对低一些的品种，各国有相应的规格标准。高效滤网的过滤材质通常由无规则排布的化学纤维（例如：聚丙烯纤维即丙纶或聚酯纤维即涤纶的无纺布）或玻璃纤维制成，直径约0.5到2.0微米，通过微观的絮状结构，主要是用来去除0.5µm以上之微粒。

High-efficiency particulate arrestance (HEPA), also sometimes called high-efficiency particulate arresting or high-efficiency particulate air, is a type of air filter. Filters meeting the HEPA standard have many applications, including use in medical facilities, automobiles, aircraft and homes. The filter must satisfy certain standards of efficiency such as those set by the United States Department of Energy (DOE). To qualify as HEPA by US government standards, an air filter must remove (from the air that passes through) 99.97% of particles that have a size of 0.3 µm.