Personal History of Dick Dillin is unknown.
He studed art at Syracuse University and found commercial illustration work with various publishers after graduation.
His first comics assignment was for "Williams Comics" doing a Korean war hero named "Buzz Bennett" for Wings Comics in 1951.
He then did work in a variety of genres (Westerns, love stories, etc.) when Al Grant, an editor at Quality Comics, called him and asked for him to work on Blackhawks. After DC licenced the publication rights, he continued to work on Blackhawks until it was cancelled.
Carmine Infantino assigned him to Justice League of America Vol 1, beginning with Justice League of America #68, beginning a twelve year tenure on the title. His last work appeared in Justice League of America #183, when he died age 50. Pencilling chores were taken over by George Pérez.