Acheulean (also spelled Acheulian) is the name of an industry of stone tools used by prehistoric hominids. It applies to the Paleolithic epoch following the Abbevillian, and it is characterized by the use of pebble, bifacial, and flake tools which included hand axes. It is named after the site, Saint-Acheul, now a suburb of Amiens in northern France. It is thought that Homo erectus is the first hominid to innovate such an industry, though this industry was used by Cro-Magnons (early Homo sapiens) and Neanderthals as well. Both of these species innovated significantly beyond the Acheulean industry in time. The Acheulean era began about 1.2 million years ago and ended about 500,000 years ago. However, the Acheulean industry continued to be used by some primitive hominid cultures up until 100,000 years ago. The primary innovation associated with Acheulean handaxes is that the stone was chipped on both sides to form two cutting edges.

These tools were more sophisticated in their conception and construction and much more effective than the tools of the Oldowan industry they succeded. Diverse materials and difficult techniques were involved in this industry which had not been seen before this period, and demonstrated that the hominids that innovated the tools were capable of a degree of forthought that can fairly be associated with the term, "human". These tools were made of stone with good fracture characteristics such as chalcedony, jasper, flint, and quartzite. Oldowan tools were used by efficient scavengers, who were still preyed upon frequently by larger animals and often bewildered by their environment. Adversely, Acheulean tools gave their masters the ability to hunt and defend themselves successfully and gave them the distinction of being equally as deadly as the greatest predators of the prehistoric Earth.

The period these tools were innovated during is usually thought to be the early Paleolithic era or the beginning of the middle Paleolithic era. The culture associated with the Acheulean industry spread throughout Europe, Africa, and Asia, during the early Paleolithic period. It flourished roughly 400,000 to 100,000 years ago in Eastern Europe and Northern Asia. The representatives of this culture were hunter-gatherers who lived in primitive communities in caves and in the open. They were able to construct fairly sophisticated shelters, and it is thought by many scientists that they had discovered the use of fire.