The intensity of the rest period in relation to environmental temperature fluctuating for Le-Conte pear cultivar was measured under laboratory conditions. Percent budbreak, accumulate chill units, ABA, GA₃ and IAA contents of buds were determined.                 Le- Conte pear cultivar started to enter into dormancy in December while its budbreak was in March. Bud opening percent corresponded positively with increasing the chilling units. ABA decreased quickly from Jan. to Mar. in Le-Conte buds, while GA₃ showed increasing level during Feb. Minimum IAA content resulted in Feb. and it reached its maximum level at budburst stage.