Morphological and cytochemical characteristics of hemocyte in the seed shrimp, Vargula hilgendorfii, were examined by light microscopy. Only a single type of hemocyte (granulocyte) was observed in the hemolymph. This hemocyte was large (18-40 μm in diameter) and irregular in shape. Two types of round granules, large granule (LG) and small granule (SG) were observed in a hemocyte. The LG was not stained with May-Grünwald nor with HE. The SG was stained with eosin, safranin, methylene blue, toluidine blue, PAS, sudan black B. Phenoloxidase activity (DOPA reaction) was detected in both SG and hyaloplasm. However, the LG was not stained with these stains. These morphological and tinctorial characteristics are compared with those of other crustacean hemocytes.