盲鳗亚纲（学名：Myxini）是一种海洋脊椎动物，过去是无颌纲(Agnatha)之下的一目，现在则是无颌总纲下的头甲鱼纲下的一亚纲。

盲鳗广泛分布于全球三大洋的温带、亚热带和热带的海域。

Hagfish, the class Myxini (also known as Hyperotreti), are eel-shaped, slime-producing marine fish (occasionally called slime eels). They are the only known living animals that have a skull but no vertebral column. Along with lampreys, hagfish are jawless; they are the sister group to vertebrates, and living hagfish remain similar to hagfish from around 300 million years ago.