黑质（Substantia nigra，拉丁语以为“黑色的物质”）是中脑的一个神经核团。黑质的位置位于中脑背盖部（tegmentum）和大脑脚之间。黑质不是一个均一的核团，它可分为结构和功能上都相差很大的黑质致密部（Substantia nigra pars compacta, SNpc），黑质网状部（Substantia nigra pars reticulata, SNpr）和黑质侧部（Substantia nigra pars lateralis）三部分。黑质是基底核的一个附属核团，是有关基底核间互相连络之重要构造。

The substantia nigra is a brain structure located in the mesencephalon (midbrain) that plays an important role in reward and movement. Substantia nigra is Latin for "black substance", reflecting the fact that parts of the substantia nigra appear darker than neighboring areas due to high levels of neuromelanin in dopaminergic neurons. It was discovered in 1784 by Félix Vicq-d'Azyr, and Samuel Thomas von Sömmerring alluded to this structure in 1791. Parkinson's disease is characterized by the death of dopaminergic neurons in the substantia nigra pars compacta.