Abstract:Under the condition that the total amount of fertilizer was fixed, two years(2015~2016) trial that single fertilizer of N、P and K were moved back for additional fertilizer was in the experimental field of the academy of agricultural sciences in Tonghua city. Tongnong 943 was used as experimental material to study the effects of different amounts of N, P and K on agronomic characters and yield of soybean, and the effects of different amounts of N, P and K on soybean production were studied. The results showed that nitrogen fertilizer topdressing when moved back has a biggest impact on soybean yield. When the nitrogen fertilizer moved back 30%, the production is at its highest level, and the yield increased by 8.1% and 11.6%, respectively in two years. However, when the amount of fertilizer was more than 45%, the yield decreased obviously. The yield difference was not significant within 30% after phosphate fertilizer was shifted back, and the yield decreased significantly after more than 45%. The effect of potash fertilizer on yield was not significant. In terms of agronomic traits, nitrogen fertilizer decreased by 30%, which significantly promoted the increase of plant height, nodes on main stem, number of pods per plant and yield per plant.Phosphate fertilizer moved back by 30%, will significantly promoted the increase of plant height. The backward topdressing of potassium fertilizer had no significant effect on agronomic traits.