The cold resistence physioloigical indexes of the leaves with two-years of Buxus microphylla introduced to Lanzhou Botanical Garden were measured and compared．Use of winter field before spraying and root irrigation and irrigating test，application of membrane permeability determination of Buxus microphylla seedling cold resistance physiological indexes.Study of pure natural plant growth regulator ‘ЭМИСТИМС’ was the concentration gradient in different period and different application methods on seedling cold resistance effect of Buxus.Introduction to provide the basis for expanding area.Introduction to provide the basis for the expansion of regional.Application of plant growth regulator in‘ЭМИСТИМС’ was enhanced cold hardiness of Buxus.The results showed that the best period was for irrigation water before twenty days of winter，optimum concentration was 100 mg/L,optimum application method was spraying and root irrigation and seedling the coldresistance was the strongest.