The studies were conducted to know the relationship between $eta$-amlyase activities and hardiness for the germinated seedlings of, winter wheat varieties which were classified with eye estimated cold resistance in field as, susceptible, moderate and resistant. These varieties were tested in continued five days from germination in four replicated split plot design. For the measurement of $eta$-amylase, improved A. K. Balls method (2) was employed. Result obtained will be summarized as follows. 1. Tested varieties showed highly significant differences in $eta$-amylase activity, while no differences were obtained between dates after germination. 2. Winter hardy varieties, Yukseung ＃3, Chin Kwang and Suwon＃85 showed higher amylase activities than the moderate hardy varieties, Jukdalma, Kangdosinryuk and Norin ＃4, while lower activities were measured in susceptible varieties, Norin ＃6, Kangdo and Norin＃12. 3. With measurement of $eta$-amylase activity, rurther detail classification to cold resistance is seemed available than eye-estimating in the field condition. 4. In accordance with testing dates, amylase activities were not so clear on 1st, 2nd, 4th and 5th days from germination, while clear differences were found on 3rd day from germination. 5. Amylase activity obtained on 3rd day after germination is considered easy and effective method to estimate cold resistance of wheat varieties with a classification standard.