The Wrong Box is a black comedy (dark comedy) novel co-written by Robert Louis Stevenson and Lloyd Osbourne, first published in 1889. The story is about two brothers who are the last two surviving members of a tontine.

The book is notable for being the first of three novels that Stevenson co-wrote with Osbourne, who was his stepson. The others were The Wrecker (1892) and The Ebb-Tide (1894). Osbourne wrote the first draft of the novel late in 1887 (then called The Finsbury Tontine), Stevenson revised it in 1888 (then called A Game of Bluff) and again in 1889 when it was finally called The Wrong Box.