Abstract: Based on the phonological data, the thermal indexes, such as the active accumulated temperature and minimum limit temperature in each growing period of soybean, were calculated for the main cultivated soybean varieties in the Heilongjiang Province, by using the Least Squares Method. The spatial distribution of thermal resource and the possible days of growing period were obtained by interpolating in the 50km50km grid based on the daily climate data in 81 stations from 1981 to 2002 in the Heilongjiang Province, and compared with the observed the active accumulated temperature and days of growing period for the main cultivated soybean varieties. The indexes for dividing zone of different mature period patterns of soybean varieties and suitable planting zones for the main cultivated soybean varieties were discussed. The soybean production zone in the Heilongjiang Province was divided into two dominant production zones (Songnen and Sanjiang plain) and one subsidiary production zone (Heihe and Yichun regions).

Key words: Soybean, Soybean, Thermal index, Active accumulated temperature, Effective accumulated temperature, Minimum limit temperature