Mikadotrochus salmianus, common name the Salmiana slit shell, is a species of large sea snail, a marine gastropod mollusk in the family Pleurotomariidae, the slit snails.
The shell is broadly trochiform, almost conical in shape. The shell is false umbilicus and spirally twisted on all sides. The shell is off-white in color with blazed red spirals. It is almost exactly conical with a broken or flattened tip. It is surrounded on all sides with furrows or traces of growth.
This species occurs in the Pacific Ocean off Japan, Fiji Islands and the Philippines.