Black triangle may refer to:
Places Black Triangle (region), across Germany, Poland and the Czech Republic, long characterized by extremely high levels of pollution Black triangle, the nickname given to the area south of Montreal affected by a long term blackout during the January 1998 North American ice storm
Other uses Black triangle (badge), a Nazi concentration camp badge worn by inmates deemed "asocial" Black triangle, an LGBT symbol reclaimed from the Nazi use Angularis nigra (Latin for 'black angle'), triangular gap between teeth Black triangle (pharmacovigilance), suffixed to the trade name of British medicines when the drug is new on the market Black triangle (UFO), a type of UFO Black triangle, several code points in Unicode Geometric Shapes