Blue (disambiguation)
Blue could refer to:

 Blue, the color
 Baby blue
 Federation blue
 Royal blue
 Tulaberry blue
 Blue alert, an alert signal used by Starfleet
 Bluebird, a type of bird
 Blue Horizon, a terraformed Federation planet
 Blue ion dye, a type of dye
 Blue match, a mode of the game Tsunkatse
 "Blue Skies", a musical composition
 Blue skin, a term used by Aenar