Harry Aaron Hollzer (November 4, 1880 – January 14, 1946) was a United States federal judge.
Born in New York, New York, Hollzer received a B.L. from the University of California in 1902 and an LL.B. from the same institution in 1903. He was in private practice in San Francisco, California from 1903 to 1924. He was a judge on the Superior Court of California from 1924 to 1931. He was a Member, Judicial Council of California from 1926 to 1931.
On January 8, 1931, Hollzer was nominated by President Herbert Hoover to a new seat on the United States District Court for the Southern District of California created by 46 Stat. 819. He was confirmed by the United States Senate on February 27, 1931, and received his commission on March 3, 1931. Hollzer served in that capacity until his death, in 1946, in Los Angeles, California.