This paper examines job gains and losses at establishment levels using micro－data in Japan from 1985 to 1992． Among total separations from establishments， about 14 percent of them was at least due to job destruction． By enterprise size， large firms with 10000r more employees frequently reallocated employment across establishments when jobs were destructed． Separations by job destruction were not observed in large firms． In small enterprises with 5－29 employees， about 30 percent of separations was generated by job destruction． About a half of gross job creation in total economy was generated within enterprises with less than 100 employees． Because of high gross job destruction as well as high gfoss job creation of smaU firms， however， there was no strong pattern of net job creation rates by enterprise size． The job destruction rate by death of fifms was low， and it might contribute to the low unemployment rate in Japan
