卡介苗（Bacillus Calmette-Guérin，简称BCG，中文名称来自于其发明者卡氏-介氏）是一种最初被用于预防结核病的疫苗。在结核病常发的国家，常推荐健康的婴儿在出生时候尽快接受一剂量的卡介苗注射。但患有艾滋病的婴儿不应该注射该疫苗。而在结核病少发的地区，在有结核病可疑病例被检测及治疗时，只有高危婴儿才会注射卡介苗。未患结核病而且并未对结核病免疫，但又长期暴露在抗药性结核菌环境下的成年人也应该注射卡介苗。

疫苗保护期的变化大，介于10到20年不等。其可以防止约20%的孩子不被感染，而疫苗可保护约一半已经受到感染的小孩病情不在恶化。卡介苗是采用皮下注射。并没有其他证据支持额外的药剂量。卡介苗有时候也会用于治疗某些类型的膀胱癌。

Bacillus Calmette–Guérin (BCG) vaccine is a vaccine primarily used against tuberculosis. In countries where tuberculosis is common one dose is recommended in healthy babies as close to the time of birth as possible. Babies with HIV/AIDS should not be vaccinated. In areas where tuberculosis is not common, only babies at high risk are typically immunized while suspected cases of tuberculosis are individually tested for and treated. Adults who do not have tuberculosis and have not been previously immunized but are frequently exposed to drug resistant tuberculosis may be immunized as well. It is also often used as part of the treatment of bladder cancer.