In this research,the trends of sea ice area (SIA) and concentrations in the Arctic and Antarctic from 1989 to 2015 were analyzed by using the climate data of passive microwave satellite sea ice concentrations (SIC). The results showed that the annual SIA had decreased in Arctic and increased in Antarctic. The ratios were -0.569*10~6 km~2·(10a)~(-1) and 0.327*10~6 km~2·(10a)~(-1),respectively,being significant at the 0.01 confidence level. The asymmetry of trends in the Arctic and Antarctic had been obvious. The total SIA had decreased, with a trend of -0.242*10~6 km~2·(10a)~(-1). The trend of annual SIC had universally declined in the Arctic,but had been obviously spatial difference in the Antarctic. The SIC had increased in the north of Weddell Sea and Ross Sea with the rate more than 10%·(10a)~(-1),but had decreased in Bellingshausen Sea and Amundsen Sea. There was obvious seasonal difference in monthly SIA variation in the Arctic. The SIA had obviously reduced from July to October,significantly in September,reaching -0.955*10~6 km~2·(10a)~(-1). The sea ice freezing time and melting time had not completely corresponded between the Arctic and Antarctic; in the Arctic melting time and freezing time had been roughly balanced,but in the Antarctic freezing time had been significantly longer than melting time. Within a year,the variation of SIA in the Antarctic had been greater than that in the Arctic,showing significant seasonal characteristics. Changing in the minimum SIA in the Arctic had been most significant,reaching -0.636*10~6 km~2·(10a)~(-1). The occurrence time of the maximum SIA in the Antarctic had moved backwards obviously,with the ratio of 0.733 pentad per decade; the occurrence time of the minimum SIA in the Antarctic had been very stable without any obvious tendency.