Romance of the Underworld is a 1928 American synchronized sound drama film produced and distributed by Fox Film Corporation. While the film has no audible dialog, it was released with a synchronized musical score with sound effects using the sound-on-film movietone process. Directed by Irving Cummings and starring Mary Astor, it was based upon a stage play called A Romance of the Underworld by Paul Armstrong. A previous version of the story was filmed as A Romance of the Underworld in 1918 by director James Kirkwood with Catherine Calvert in Astor's part.

• Mary Astor as Judith Andrews
• Ben Bard as Derby Dan Manning
• Robert Elliott as Edwin Burke
• John Boles as Stephen Ransome
• Oscar Apfel as Champagne Joe
• Helen Lynch as Blonodie Nell
• William H. Tooker as Asa Jenks

The film featured a theme song titled "Judy", which was composed by Irving Kahal, Sammy Fain, and Pierre Norman.

The Motion Picture Producers and Distributors of America, formed by the film industry in 1922, regulated the content of films through a list of subjects that were to be avoided. While Mary Astor portrayed a prostitute in Romance of the Underworld, this was acceptable as prostitution was not explicitly barred so long as it was not forced (i.e., white slavery) and aspects of her work was not shown in the film.^[1] Here the work of Astor's character is ambiguously described as being a "hostess."

Romance of the Underworld is extant at the Museum of Modern Art.^[2][3] And also in a European archive.^[4]

• List of early sound feature films (1926–1929)