The material upon which this study was based was collected from the Xisha Islands by the Institute of Oceanology, Academia Sinica in May, 1975 and by the South China Sea Institute of Oceanology, Academia Sinica in May to June 1974 and in March to April, 1975.Nineteen species of phaeodarian radiolaria (6 uncertain ), belonging to 9 families and 14 genera, have been identified (see list of species in text). As the investigated region is limited to areas close to the Xisha Islands with depths not more than 1000 meters, the number of species found is very few and their occurrence is in low frequencies. Most of the species are warm water forms.