Pendejo Cave is a geological feature and archaeological site located in southern New Mexico about 20 miles east of Orogrande. Archaeologist Richard S. MacNeish claimed that human occupation of the cave pre-dates by tens of thousands of years the Clovis Culture, traditionally believed to be one of the oldest if not the oldest culture in the Americas.

Pendejo Cave was discovered in 1978, and twelve years later, in early 1990, the first archaeological expedition headed by MacNeish excavated the site. Another excavation occurred one year later, in late winter and early spring of 1991. Clovis (c. 11,000 BCE) tools were found in the cave, along with tools from later Native societies. Unifacial shavers, utilized flakes, and other artifacts were uncovered and attributed to various eras, along with several examples of worked bone, including a bone awl made from the scapula of a horse, and a knife made from a rib bone.

MacNeish claimed to have found even earlier Native American artifacts in the cave. A total of 111 chipped tools were found throughout the formation in three complexes. He estimated the oldest may date back as far as 75,000 years.

According to MacNeish, he found 3 pre-Clovis strata in the cave that he named, from oldest to youngest, the Orogrande, the McGregor, and the North Mesa.

As of 2004, the early dating of the discoveries at Pendejo Cave has been discounted by many archaeologists. Faunal remains in the cave had been dated to possibly as old as 55,000 years, but the manufacture and dating of the chipped stones and other alleged artifacts of human origin were disputed.

In 2015, William Farrand, in his review of MacNeish and Libby's 2004 book, noted the abundance and integrity of the data as provided by the authors. According to Farrand," it is difficult to avoid accepting the hypothesis of pre-Clovis Paleoamericans in the American Southwest prior to 37,000 or 55,000 B.P."