All four species of the soft scale insect genus Pulvinaria Targioni Tozzetti (Hemiptera: Coccomorpha: Coccidae) known from the Ryukyu Islands, Japan, are reviewed. For each species, the detailed morphology of the adult female is redescribed from specimens recently collected in the Ryukyu Islands and is compared with previous descriptions. A key to the species of Pulvinaria in the Ryukyu Islands is provided. A table of diagnostic morphological character states of the reviewed species and the type species of the genus, P. vitis (Linnaeus, 1758), is provided for use in future taxonomic revision of the genus; this comparison indicates that all four species of Pulvinaria in this region and the type species of the genus, P. vitis can be distinguished clearly from each other by several diagnostic morphological character states.