Sea potato may refer to:
Biology Colpomenia peregrina, a species of brown algae more commonly known as oyster thief or bladder weed Leathesia marina, formerly Leathesia difformis, another species of brown algae more commonly known as sea cauliflower Species of littoral sea urchins, especially heart urchins Echinocardium cordatum, a specific species of urchin, commonly known as common heart urchin. Echinocardium flavescens, called the yellow sea potato
Geology Manganese nodule, also known as polymetallic nodules or ferromanganese modules, mineral concretions on the sea bottom