蚊香是含有除虫菊精类成分的线香。在蚊香的一端点火后，蚊香在不完全燃烧下，释放烟雾有杀灭蚊子的功效。

宋代《格物粗谈》中记载：“端午时，收贮浮萍，阴干，加雄黄，作纸缠香，烧之能祛蚊虫。”古人很早就有“燃火绳”法，即把蒿草、艾草编织成草绳湿润后点燃，发出的浓烟可以驱蚊。

早期的蚊香是粉末状或棒状的，现在一般制成漩涡形状，漩涡状蚊香其实总长75公分，使蚊香延长燃烧时间之余，又能减少面积。这是大日本除虫菊公司（大日本除虫菊株式会社）的创办人上山英一郎的妻子所提出的。据说她在仓库里看到一条盘成一团的蛇，吓了一跳，马上跑到了丈夫身边告诉他这件事情，之后这个轶事便成了蚊香的形状的由来。

A mosquito coil is a mosquito repelling incense, usually shaped into a spiral, and typically made from a dried paste of pyrethrum powder. The coil is usually held at the center of the spiral, suspending it in the air, or wedged by two pieces of fireproof nettings to allow continuous smoldering. Burning usually begins at the outer end of the spiral and progresses slowly toward the centre of the spiral, producing a mosquito-repellent smoke. A typical mosquito coil can measure around 15 cm in diameter and lasts around 8 hours. Mosquito coils are widely used in Asia, Africa, South America and Australia.