Abstract: Abstract: In order to reveal the regulation of the walnuts’flowering and spreading-powder and to provide basis for improving effects on their pollination and fecundation and arranging pollination trees scientifically, the study was done on the blooming phenophase, pollen viability and the regulation of spreading-powder about the main planted varieties of the walnut in Xinjiang. Using the two main-planted early bearing walnuts varieties of ‘Xinxin 2’ and ‘Wen 185’ in Xinjiang as materials, these studies were done on computing the quantities of pollen, measuring the pollen’s vitality, observing the blossom phenological, measuring the quantities of spreading-powder in total and in a day during the florescence. The results indicated that the numbers of anther in every bud about the‘Wen185’and ‘Xinxin2’ were average 77000 and 71400 grains individual. (2) The two main planted varieties’ quantity of spreading-powder were consistent in space: southern>eastern>western> northern>internal successively, but in the same direction: it was central> internal> outside. (3) The optimum temperature about the two main varieties’ spreading-powder was 20℃ to 24℃. (4) The male and female flowers of ‘Xinxin2’ and‘Wen185’ were synchronization, which was about 4 days. The flowers of ‘Xinxin 2’ could be self-pollination, but the female flowers of ‘Wen185’ lost its receptivity, so failed to be self-pollination. The temperature played a important role in walnuts’ spreading-pollen. It existed difference in spreading-pollen when the male flowers distributed the different space in tree crown. The ‘Xinxin 2’ could be self-pollination under the natural conditions.