The blue crayfish is Procambarus alleni, of which an electric blue morph is common in aquaria.
Blue crayfish may also refer to:
- Cherax quadricarinatus - tropical blue crayfish, or blue lobster, also common in aquaria
- Cambarus monongalensis - Blue or Mononghela crayfish
- Euastacus sulcatus - Blue or Lamington crayfish, from Australia
Also, three North American burrowing crayfish have 'blue' in their common name:
- Cambarus cymatilis - Conasauga blue burrower
- Cambarus harti - Piedmont blue burrower
- Cambarus loughmani - Blue Teays mudbug