A teaser trailer for the film was shot long before the movie was in production. It featured Bruce Campbell (filling in for the role later played by Dan Hedaya) bloody and crawling down the road, just like the movie.
Holly Hunter had auditioned for the role of Abby, but turned it down because she was performing a play in New York at the same time. So she encouraged her roommate Frances McDormand to go and audition for the role.
While M. Emmet Walsh's character is named "Loren Visser" in the screenplay, his character is never actually named in the film (his cigarette lighter has "Loren" written on it), and he is listed as "Private Investigator" in the credits.
The title is based on a phrase from the Dashiell Hammett novel 'Red Harvest', in which "blood simple" is a term coined to describe the addled, fearful mindset people are in after a prolonged immersion in violent situations.
On the advice of Sam Raimi, the Coens went door-to-door showing potential investors a two minute 'trailer' of the film they planned to make. They ultimately raised $750,000 in a little over a year, enough to begin production of the movie.
The finished film was brought to L.A. and shown to the major studios, and all passed on the movie. Later that year it was accepted into the 1984 New York Film Festival, and then shown at the Toronto Film Festival, where a deal was made with Circle Films to distribute the movie domestically.