拉格朗日括号是一种与泊松括号关系密切的运算，1808年至1810年间由约瑟夫·拉格朗日最早用于经典力学之中。不过与泊松括号相比，拉格朗日括号在今日已不常使用。

令(q₁, …, q_n, p₁, …, p_n)为相空间中的正则坐标，且每一个坐标都可表示为两个变量u与v的函数，则u和v的拉格朗日括号为：

Lagrange brackets are certain expressions closely related to Poisson brackets that were introduced by Joseph Louis Lagrange in 1808–1810 for the purposes of mathematical formulation of classical mechanics, but unlike the Poisson brackets, have fallen out of use.