Blue butterfly may refer to:

• Lycaenidae, a family of butterflies
  • Polyommatinae, a subfamily consisting of the blue butterflies
    • Common blue (Polyommatus icarus)
    • Large blue (Phengaris arion)
    • Small blue (Cupido minimus)
  • Euphilotes, a subfamily consisting of blue butterflies
    • El Segundo Blue (Euphilotes battoides)
• Blue morpho (disambiguation), several species in the genus Morpho

• The Blue Butterfly, Canadian film
• Blue Butterfly (album), JPOP album

• All pages with titles containing blue butterflies
• All pages with titles containing blue butterfly