The original script was adapted from a story by pornographic film producer David Grant and was much more sexually explicit. Director Val Guest disliked its sexual content and made numerous revisions to tome t down before agreeing to film it.
Au Pair Girls was director Val Guest's first sex comedy. Unfamiliar with the genre, he decided to view a number of foreign sex comedies in preparation and turned to ex-BBFC censor John Trevelyan for suggestions since he had seen most of them during his time as a censor.
John Le Mesurier (Mr. Wainwright) and Rosalie Crutchley (Lady Tryke) received "with guest appearances by" credits.