Blue on blue may refer to:
Music "Blue on Blue" (song), a 1963 hit song recorded by Bobby Vinton Blue on Blue (Bobby Vinton album), 1963 Blue on Blue (Leigh Nash album), 2006 "Blue on Blue" (James Blunt song), a 2013 song by James Blunt "Blue on Blue" (Pet Shop Boys song), a song by the Pet Shop Boys
Television "Blue on Blue" (Ugly Betty), an episode of Ugly Betty "Blue on Blue" (Under the Dome), an episode of Under the Dome
Other Blue on Blue (book), a 2017 book about police misconduct by Charles Campisi and Gordon Dillow Blue on blue (military), inadvertent firing towards an allied NATO military force