Abstract: Based on the. 10-years surface synoptic charts (1951 to 1960),monthly frequencies of cyclones and low pressure centers passing 2.5°×2.5° latitude-longitude grids in Eastern Asia are analized and the main tracks are studied and classified. The cyclones are most frequent in middle part of Mongolia and north-east China, and none south of 20°N. Most of the low pressures occurred south of 45°N are very weak. Spring is the season of cyclonic activity.