数学中，重心坐标是由单形（如三角形或四面体等）顶点定义的坐标。重心坐标是齐次坐标的一种。

设v₁, ..., v_n是矢量空间V中一个单形的顶点，如果V中某点p满足，

那幺我们称系数（λ₁, ..., λ_n）是 p关于v₁, ..., v_n的重心坐标。这些顶点自己的坐标分别是（1, 0, 0, ..., 0），（0, 1, 0, ..., 0）, ...,（0, 0, 0, ..., 1）。重心坐标不是惟一的：对任何不等于零的k，（k λ₁, ..., k λ_n）也是p的重心坐标。但总可以取坐标满足 λ₁ + ...+ λ_n = 1，称为正规化坐标。注意到定义式在仿射变换下不变，故重心坐标具有仿射不变性。

In geometry, the barycentric coordinate system is a coordinate system in which the location of a point of a simplex (a triangle, tetrahedron, etc.) is specified as the center of mass, or barycenter, of usually unequal masses placed at its vertices. Coordinates also extend outside the simplex, where one or more coordinates become negative. The system was introduced (1827) by August Ferdinand Möbius.