亚非欧大陆、亚欧非大陆或亚欧非大陆指的是亚洲、欧洲、非洲三个大陆的合称。

在地理上，直到苏伊士运河开通以前，三个大陆是相连的。在文化上，欧洲、亚洲和北非的关系比较接近。在地缘政治学上，亚欧非大陆的主体 （不包括菲律宾、印尼、日本、英伦三岛、马达加斯加等岛屿）被称为「世界岛」。加上岛屿就称为旧大陆。

在地质学上，非洲原来是冈瓦纳古陆的一部分，后来才与亚欧大陆相撞。预计60万年后，非洲将与欧洲连成一体，地中海将与大西洋分开。5千万年后，地中海会消失，变成山脉。

Afro-Eurasia, Afroeurasia, or Eurafrasia, known in antiquity as the Ecumene and most commonly known since the Age of Exploration as the Old World, is the largest landmass on Earth, primarily in the Northern and Eastern Hemispheres. The term is a portmanteau of its constituent parts: Africa and Eurasia, the latter divided into Europe and Asia. Afro-Eurasia encompasses 84,980,532 square kilometers (32,811,166 sq mi) and has a population of approximately 6 billion people which is roughly 85% of the world population. In geopolitical contexts, it is sometimes known as the World Island, a term coined by H.J. Mackinder.