A sea serpent is a mythological sea creature either wholly or partly serpentine.
Sea Serpent or The Sea Serpent may refer to:
- Sea Serpent (clipper), 1850 clipper ship which sailed in the San Francisco and China trade
- Sea-Serpent, a steam yacht, formerly HMS Squirrel (1904)
- Sea Serpent (roller coaster), at Morey's Piers in Wildwood, New Jersey
- Sea Serpent (roller coaster element), a double-inversion element with vertical loop halves connected by half corkscrews
- Sea Serpent Cove, a cove in the South Sandwich Islands
- The Sea Serpent, 1901 adventure novel by Jules Verne
- The Sea Serpent (aka Hydra, the Sea Monster), a 1984 Spanish horror film directed by Amando de Ossorio
- Sea Serpent, a variant of the Gabriel (missile) developed by Israel's IAI and Thales
- Sea Serpent (ASW), a US Anti Submarine system.