In this paper, the chlorine and sulfate nucleus data, Observed in Yongxing (Xisha islands) during May, 1987, are analyzed, The main results are:1) The average concentration of chlorine ion nuclei is 618 per litre and the average salt content is 57.2μg/m3
. Both values are between the data observed in Putou and Haiyang island; the spectrum type shows quasiunimodal and exponential lapse rate, The average concentration of sulfate ions is 15 per litre ,the mean salt content is 23.8 μg/m3
,and the spectral show multimodal types, more wider than that of chlorine ions, the largest dried diameter reaches 59μ.2) Both concentrations of sulfate ions and chlorine ions decrease as the distances to seaside increase.3) The distribution of sea-salt nuclei has very good correlations with wind speed and wave height. Chlorine ion nuclei appear largest value at 14 o'clock, Their diurnal variations are relative to tide.