沙蟹（学名：Ocypode）是一种常见的海滩螃蟹，分布在很多国家。其特征为有一只螯比另一只大，但是没有招潮蟹属螃蟹差异那幺明显。

沙蟹生活在热带和亚热带地区沙滩。它们使用鳃呼吸，通过海水定期保持湿润。它们还必须返回到海洋产卵。

成年沙蟹挖很深的洞穴，一个很长的信道的尽头是房间，偶尔会有两个入口。一天中最热的时候它们呆在洞里，冬天最冷的时候也是如此。它们通常在夜晚出没，捕食贝类等。

Ocypode is a genus of ghost crabs found in the sandy shores of tropical and subtropical regions throughout the world. They have a box-like body, thick and elongated eyestalks, and one claw is larger than the other in both males and females. They inhabit deep burrows in the intertidal zone. They are primarily nocturnal, and are generalist scavengers and predators of small animals. The genus contains 21 species.