Abstract: For the purpose of the application of controlled release nitrogen the best dosage. Under field condition, set six treatments, T1 no N fertilizer, T2 conventional fertilization (basal dressing), T3 conventional urea (basal dressing + topdressing), T4 controlled release urea 100%, T5 controlled release urea 90%, T6 controlled release urea 80%. A study on the effects of controlled release nitrogen fertilizer on soil nitrate nitrogen and plant total nitrogen content and yield of corn, Results show that the soil nitrate nitrogen and total nitrogen content of the straw with the development of growth period is on the decline, the highest content and jointing stage. Controlled release nitrogen fertilizer processing various nitrogen filling stage to maturity levels than conventional fertilization treatment. Controlled release nitrogen fertilizer treatment improved the corn aboveground dry matter weight of different growth period, and from jointing stage to mature stage, controlled release urea 100%, controlled release urea 90% treatment of aboveground dry matter weight is higher than common urea, and controlled release of urea 90% is the largest. Reasonable controlled release nitrogen fertilizer dosage increased stem diameter of corn and grain numbers per spike, reduce bald tip length of corn. But the hundred grain weight had little change. Controlled release urea 90% with the highest yield, 8637.6 kg/hm2, and nitrogen reached significant difference compared with conventional fertilization level.