William Simmian "Willis" Kienholz (October 10, 1875 – September 20, 1958) was an American college football player and coach. He served one-year stints as the head coach at six different colleges: Lombard College in Galesburg, Illinois (1903), North Carolina College of Agriculture and Mechanic Arts—now North Carolina State University (1904), the University of Colorado at Boulder (1905), University of North Carolina at Chapel Hill (1906), Auburn University (1907), and Washington State University (1909). Kienholz played football at the University of Minnesota in 1898 and 1899.

In 1902, Kienholz was an assistant football coach as his alma mater, Minnesota, working under head coach Henry L. Williams. During that season, he was also slated at the head coach at Lombard College in Galesburg, Illinois.^[1] The next year he was again the head football coach at Lombard, leading his team to a championship of Illinois colleges.^[2]

In 1904, Kienholz coached at North Carolina A&M, and compiled a 3–1–2 record. In 1905, he coached at Colorado, and compiled an 8–1 record. In 1907, he coached at Auburn, and compiled a 6–2–1 record. In 1909, he coached at Washington State, and compiled a 4–1 record.

Kienholz later served as the director of vocational training for the public schools of Los Angeles, California. He died on September 20, 1958, in Seattle, Washington.^[3]