Soldier crab is a term used in different parts of the world for different crustaceans:

• Pagurus bernhardus, a European hermit crab
• Coenobita clypeatus, a Caribbean hermit crab
• Dotilla myctiroides, a true crab from South-east Asia
• several species of the genus Mictyris, an Indo-West Pacific genus of crabs:
  • In Australia, the term soldier crab generally refers to Mictyris longicarpus