He was the older brother of playwright Neil Simon. The elder Simon wrote for television shows including Your Show of Shows, The Colgate Comedy Hour, The Phil Silvers Show, Make Room for Daddy, My Three Sons, The Carol Burnett Show, Kraft Music Hall, Diff'rent Strokes, and The Facts of Life. He later became a comedy teacher.
Woody Allen said about Simon, "I've learned a couple of things on my own since and modified things he taught me, but everything, unequivocally, that I learned about comedy writing I learned from him".
Jimmy Boyd, "Being around Danny always makes me and everyone else happy. He is always up and positive, and he sees humor in absolutely everything. It is endless funny one-liners. In rehearsal I could read the same comedy line a hundred times, and Danny would be laughing".
Simon was married to Arlene Friedman from 1953 to 1962. The couple had two children, Michael and Valerie. In 2011, Michael Simon was appointed by President Barack Obama to be a judge on the United States District Court for the District of Oregon.
- Bernstein, Adam (July 28, 2005). "TV Comedy Writer Danny Simon Dies". The Washington Post.
- Neuhaus, Cable (June 27, 1983). "Comedy Writer Danny Simon Nurses An Old Wound—the Frustration of Being Neil Simon's Brother". People. Retrieved February 1, 2012.
- Law, Adair (Fall 2011). "Oregon Welcomes New Federal Judges" (PDF). Oregon Benchmarks. Archived from the original (PDF) on December 22, 2012. Retrieved February 1, 2012.