毒麦（学名：Lolium temulentum）禾本科黑麦属的植物。

毒麦是一年生草本植物，秆丛生，排列较疏，可以长到一米高；叶子薄而狭长；小穗有4－5小花，外稃有芒；小穗背腹面对向穗轴呈穗状花序，长达10～25厘米；颖果呈紫色。

Lolium temulentum, typically known as darnel, poison darnel, darnel ryegrass or cockle, is an annual plant that forms part of the Poaceae family and part of the Lolium genus. The plant stem can grow up to one meter tall, with inflorescence in the ears and purple grain. It has a global distribution.