Lady Audley's Secret is involved in a subplot of Betsy and Tacy Go Downtown, the fourth book in the Betsy-Tacy series by Maud Hart Lovelace. Betsy has read it and other books in the same genre, and aspires to write similar works.
In the Agatha Christie short story Greenshaw's Folly Miss Greenshaw hides her will in a copy of Lady Audley's Secret remarking it was a "best seller in its day".