Quite uniquely, director François Truffaut chose to shoot the film almost completely in chronological order. The reasoning for this was that he found the relationship between the two main characters so important, he wanted it to develop in a natural way. Truffaut actually spent the nights re-writing the scenes he would film the next day, to follow the dynamics between the leading couple.
The film is dedicated to director Jean Renoir. The dedication is visible at the beginning and signed by Truffaut.
The original French title is spelled "La Sirène du Mississipi" (one P) in some sources, and "La Sirène du Mississippi" (two Ps) in other sources.
The book that Louis finds in the isolated cabin near the end of the movie is "La Peau de chagrin" ("The Wild Ass's Skin"), by Honore de Balzac. According to Wikipedia, "Set in early 19th-century Paris, it tells the story of a young man who finds a magic piece of shagreen (untanned skin from a wild ass) that fulfills his every desire. For each wish granted, however, the skin shrinks and consumes a portion of his physical energy."