谷物法（Corn Laws）是一道于1815年至1846年强制实施的进口关税，借以“保护”英国农夫及地主免受来自从生产成本较低廉的外国所进口的谷物的竞争。要注意的是，在英式英语里，“玉米”（corn）这个词语泛指所有谷物，与美式英语专指玉米的意思有所不同。

根据David Cody教授的说法：

“谷物法是用来保护英国地主之利益；其手段为，当谷物价格下降到一定程度时，即鼓励出口并限制进口。谷物法最终在「反谷物法联盟」的军事动乱中被废除了；此联盟在一八三八年时于曼彻斯特成立，宣称谷物法增加了工业生产成本。经过一连串的竞争之后，反谷物法者终于在一八四六年得以遂其心愿，这也象征了英国中产阶级在政治权力中一项重要的胜利。”

The Corn Laws were measures enforced in the United Kingdom between 1815 and 1846, which imposed restrictions and tariffs on imported grain. They were designed to keep grain prices high to favour domestic producers. The laws did indeed raise food prices and became the focus of opposition from urban groups who had far less political power than rural Britain. The Corn Laws imposed steep import duties, making it too expensive to import grain from abroad, even when food supplies were short. The laws were supported by Conservative landowners and opposed by Whig industrialists and workers. The Anti-Corn Law League was responsible for turning public and elite opinion against the laws. It was a large, nationwide middle-class moral crusade with a Utopian vision, according to historian Asa Briggs; its leading advocate Richard Cobden promised that repeal would settle four great problems simultaneously: