真鳄亚目（Eusuchia）是个鳄鱼演化支，首次出现于白垩纪晚期。目前所有的现存鳄鱼，以及牠们的绝种近亲，都属于真鳄亚目。

与原始的鳄形超目不同，真鳄类具有骨质的次生颚。这个特征使得现存鳄鱼可以浸泡在水面下，以口鼻部前端的鼻孔呼吸。真鳄类的内鼻孔完全由翼骨环绕者。

The Eusuchia ("true crocodiles") are a clade of crocodylomorphs that first appears in the Early Cretaceous with Hylaeochampsa. Along with Dyrosauridae and Sebecosuchia, they were the only crocodyliformes who survived the K-T extinction. Since the other two clades died out 35 and 11 million years ago, all living crocodilian species are eusuchians, as are many extinct forms.