Dicyema shimantoense is a parasitic worm of the phylum Dicyemida.

It is a vermiform mesozoan parasite that infects the renal appendages of the cephalopod Octopus sasakii.

A study from 2000-06 used 59 specimens obtained from fishermen at Tosa Bay and Kii Strait in Japan.

Examination of the calotte (the anterior ends of dicyemids ) is required to distinguish them.

D. shimantoense inserts the conical calottes into intracellular folds of renal appendages.