Buttonwillow (formerly, Buena Vista) is a census-designated place (CDP) in the San Joaquin Valley, in Kern County, California, United States. Buttonwilliow is located 26 miles (42 km) west of Bakersfield, at an elevation of 269 feet (82 m). The population was 1,508 at the 2010 census, up from 1,266 at the 2000 census. The center of population of California is located in Buttonwillow.
The town was originally called Buena Vista when it was laid out in 1895, but the name quickly became Buttonwillow.
Buttonwillow was named for the buttonbush (Rubiaceae cephalanthus occidentalis), which resembles the willow. A lone button bush served as a landmark on an old trans-valley trail, and was used by ancient Yokut Indian as a meeting place, later becoming the site of settlers' stock rodeos. This tree is listed as California Historical Landmark No. 492. This landmark is now known as the Buttonwillow Tree.