Warning sign may refer to:

A traffic warning sign is a type of sign which indicates a potential hazard, obstacle or condition requiring special attention Safety sign, a sign that warns of a hazard, prohibited action, required action or equipment, and locations of safety equipment or exits Hazard symbol, recognisable symbols designed to warn about hazardous or dangerous materials, locations, or objects Warning label, label attached to a product (such as chemicals or tobacco) warning the user about risks associated with its use

Media Warning Sign (film), a 1985 American film directed by Hal Barwood "Warning Signs", an episode of the TV series The Walking Dead "Warning Sign" (song), by Eddie Rabbitt, 1985 "Warning Sign", by Coldplay from A Rush of Blood to the Head, 2002 "Warning Sign", by Nick Heyward, 1984 "Warning Sign", by Talking Heads from More Songs About Buildings and Food, 1978