Morphological characteristics of fixed phagocytes（FP）in the ventral abdominal ganglion, hematopoietic tissue（HT）and gill of kuruma prawn Marsupenaeus japonicus were examined by electron microscopy. The FP in these tissues did not phagocytose foreign substances such as colloidal carbon and latex beads injected into abdominal muscle of the prawn. However, electron-dense materials which considered as residual body after phagocytosis were observed in the FP. The FP in the ganglion and HT had a few cell processes and small number of fine granules. Podocyte in the gill（branchial podocyte) contained residual body in the large vacuoles. Therefore, the podocyte is fixed phagocyte in the wide sense. After injection of the foreign substances, hemocytes formed mesh structure and phagocytosed the substances in the lumen of gill. This finding indicates that the lumen of gill is the important space for defense mechanism by hemocytes.