Abstract: To understand the effect of different sowing dates on the growth and yield of soybean is important for seeking suitable sowing date, improving quality and achieving efficient production. The main soybean cultivar in Harbin, Heilongjiang was used as test material, and three sowing date treatments (S1 was May 1st, S2 was May 10th and S3 was May 21st) were conducted to study soybean growth and yield under different sowing dates. The results showed that the growth duration of S1 and S2 treatment was lengthened, dry matter accumulation and allocation and growth rate of S1 and S2 treatment were significantly higher than that of S3 treatment during seed filling period to mature period, transfer amount of dry matter accumulation to fruit was increased, the yield increased by 230.6 and 317.7 kg/hm2, respectively; S2 was the optimum among the three treatments, the utilization degree of climate resources such as water and heat was higher. The suitable sowing date of soybean was May 8th to May 10th in Harbin, but soil moisture or the first saturating rain in spring should be considered for the optimum sowing date, to promote soybean growth and development and improve the yield.