Abstract: The growth and reproduction of common buckwheat are affected by many environmental factors. Seasonal variations of temperature, sunlight and water supply obviously affect the yields. In order to reveal the suitable sowing periods in different geographical areas of Shanxi Province and to investigate the effect of different sowing dates on major yield traits of common buckwheat, we planted‘Mudanqiao’in different seasons, and recorded the sowing date, maturity date, growth period and measured the height of plant, nodes of main stem, grain weight per plant, weight of one thousand grains, yield per plot, etc. Furthermore, we set up the regression equation by mathematical statistics. Our results showed that the growth and reproduction of ‘Mudanqiao’were not sensitive to sunlight and water, but they were greatly affected by the temperature in different seasons. The higher the average temperature from seedling to flowering was, the shorter the growth period was and the fewer the branches of main stem were, meanwhile, the weight per plant and yield per plot were increased. Buckwheat would grow fast like other crops when the temperature went up in the stage of sowing to seedling. The most suitable temperature in the filling stage was between 18-22℃, and the most suitable sowing date was from July 7 to 20 in Taiyuan area of Shanxi Province.