二烯丙基二硫（英语：diallyl disulfide，缩写DADS）又叫4,5-二硫杂-1,7-辛二烯（4,5-dithia-1,7-octadiene），是一种有机硫化合物，常见于葱属植物中，如洋葱和大蒜。二烯丙基二硫、二烯丙基三硫和二烯丙基四硫是大蒜油的主要成分。DADS是一种淡黄液体，可溶于水，含有强烈蒜臭味。大蒜或者其他葱科植物切开后就会释放蒜素，蒜素分解后可得到DADS，它对大蒜健康生长有很多好处，但它也是一种抗敏原，会导致大蒜过敏。通过高度稀释后的DADS也可以用作食物调味料。

Diallyl disulfide (DADS or 4,5-dithia-1,7-octadiene) is an organosulfur compound derived from garlic and a few other genus Allium plants. Along with diallyl trisulfide and diallyl tetrasulfide, it is one of the principal components of the distilled oil of garlic. It is a yellowish liquid which is insoluble in water and has a strong garlic odor. It is produced during the decomposition of allicin, which is released upon crushing garlic and other plants of the Alliaceae family. Diallyl disulfide has many of the health benefits of garlic, but it is also an allergen causing garlic allergy. Highly diluted, it is used as a flavoring in food. It decomposes in the human body into other compounds such as allyl methyl sulfide.