The Peloncillo Mountains of Cochise County (Spanish language pelo, hair, pelon, hairless, bald; peloncillo, Little Baldy) is a mountain range in northeast Cochise County, Arizona. A northern north-south stretch of the range extends to the southern region of Greenlee County on the northeast, and a southeast region of Graham County on the northwest. The north stretch of the Peloncillo's forms the border between the two counties. It lies east and northeast of the Willcox Playa, and the San Simon Valley.