Crystal skulls are human skull hardstone carvings made of clear or milky white quartz (also called "rock crystal"), claimed to be pre-Columbian Mesoamerican artifacts by their alleged finders; however, these claims have been refuted for all of the specimens made available for scientific studies. The results of these studies demonstrated that those examined were manufactured in the mid-19th century or later, almost certainly in Europe, during a time when interest in ancient culture abounded. The skulls appear to have been crafted in Germany, quite likely at workshops in the town of Idar-Oberstein, which was renowned for crafting objects made from imported Brazilian quartz in the late 19th century.

Despite some claims presented in an assortment of popularizing literature, legends of crystal skulls with mystical powers do not figure in genuine Mesoamerican or other Native American mythologies and spiritual accounts. The skulls are often claimed to exhibit paranormal phenomena by some members of the New Age movement, and have often been portrayed as such in fiction. Crystal skulls have been a popular subject appearing in numerous science fiction television series, novels, films, and video games.