原爆点（英文称为Ground Zero，直译为「地面零点」）为一军事术语，狭义指原子弹爆炸时投影至地面的中心点，广义则可指任何大规模爆炸的中心点。

一般提及「原爆点」时，常是特指1945年发生的广岛市原子弹爆炸、或长崎市原子弹爆炸的爆炸中心点。而2001年发生九一一事件后，也使用「Ground Zero」来指称在恐怖攻击中遭到摧毁的世界贸易中心双子星大楼原址。此外，美国国防部所在地五角大厦的中庭广场，也被暱称为「Ground Zero」，这是因冷战时期曾假设苏联如对美国进行核子武器攻击，五角大厦会成为攻击目标之一。

In terms of nuclear explosions and other large bombs, the term "ground zero" (sometimes also known as "surface zero") describes the point on the Earth's surface closest to a detonation. In the case of an explosion above the ground, ground zero refers to the point on the ground directly below the nuclear detonation and is sometimes called the hypocenter (from Greek ὑπο- "under-" and center). Generally, it is also used in relation to earthquakes, epidemics, and other disasters to mark the point of the most severe damage or destruction. The term is distinguished from the term zero point in that the latter can also be located in the air, underground, or underwater.