Clingerman was born Mildred McElroy in Allen, Oklahoma and her family moved to Tucson, Arizona in 1929. She graduated from Tucson High School and attended the University of Arizona. She married Stuart Clingerman in 1937.
Most of her short stories were published in the 1950s in The Magazine of Fantasy & Science Fiction, edited by Anthony Boucher. Boucher included her story "The Wild Wood" in the seventh volume (1958) of The Best from Fantasy and Science Fiction and dedicated the book to her, calling her the "most serendipitous of discoveries.":252–3 Her science fiction was collected as A Cupful of Space in 1961. She also published in mainstream magazines like Good Housekeeping and Collier's. Her story "The Little Witch of Elm Street" appeared in Woman's Home Companion in 1956.:374
- "Funeral Notices: Clingerman, Mildred McElroy". Arizona Daily Star. March 1, 1997. pp. 16A.
- "Mildred Clingerman - Summary Bibliography". The Internet Speculative Fiction Database. Retrieved August 16, 2011.
- Davin, Eric Leif (2006). Partners in Wonder: Women and the Birth of Science Fiction 1926–1965. Lexington Books. ISBN 0-7391-1266-X.
- Robert Reginald (January 2009). Contemporary Science Fiction Authors. Wildside Press LLC. pp. 53–54. ISBN 978-1-4344-7858-0. Retrieved 16 August 2011.