低放射性废物（英文：Low-level waste，缩写：LLW）是除中等放射性废物、高放射性废物、乏燃料、超铀元素废料以及浓缩铀工厂边角料（uranium mill tailings）之外所有放射性核废料的总称。如果低放射性废物同其他有害化学品混在一起，则在处理、储藏和废弃处置时必须同时满足低放射性废物和有害化学品的监管要求。在技术上，各国对低放射性废物的放射性有不同的数值定义。国际原子能机构提供划分方面的指导。

Low-level waste (LLW) is nuclear waste that does not fit into the categorical definitions for intermediate-level waste (ILW), high-level waste (HLW), spent nuclear fuel (SNF), transuranic waste (TRU), or certain byproduct materials known as 11e(2) wastes, such as uranium mill tailings. In essence, it is a definition by exclusion, and LLW is that category of radioactive wastes that do not fit into the other categories. If LLW is mixed with hazardous wastes, then it has a special status as mixed low-level waste (MLLW) and must satisfy treatment, storage, and disposal regulations both as LLW and as hazardous waste. While the bulk of LLW is not highly radioactive, the definition of LLW does not include references to its activity, and some LLW may be quite radioactive, as in the case of radioactive sources used in industry and medicine.