To explore the effects of different tillage methods and straw returning to soil on soil total nitrogen content and wheat yield，a long-term field experiment was conducted at the Yangzhou University experimental farm in autumn 2001. A total of 6 treatments were set up in the experiment，including no-tillage and straw returning of rice and wheat continuously(NTS)，convention tillage of wheat and no-tillage of rice(RT1)，conventiontillage of rice and no-tillage of wheat(RT2)，convention tillage and straw returning in rice and wheat continuously(CTS)，minimum tillage and straw reduce returning in rice and wheat continuously(MTS)，convention tillage and no straw returning in rice and wheat continuously(CT). After the wheat was harvested，the wheat yield was measured and the total nitrogen content in the soil was determined. The results were as follows:(1)Continuous straw returning treatment significantly increased soil total nitrogen content. The total nitrogen content in the plough layer of CTS and MTS treatments increased by 12.63% and 14.74%，respectively，compared with the CT treatment；(2)NTS treatment increased the total nitrogen content of the topsoil by 24.53%，but reduced it in the lower topsoil by 15.49%. Both CTS and MTS treatments effectively increased the total nitrogen content of the topsoil.(3)Long-term no-tillage treatment reduced wheat yield to a certain extent，being 2.07% lower than that of the CT treatment at the 20-year average. However，the average wheat yield of the RT1，RT2，CTS and MTS treatments at the 20-year average increased by 1.17%，2.20%，1.76% and 1.95%，respectively，compared with the CT treatment. Therefore，the combination of rotational tillage，reduced tillage and ploughing with an appropriate amount of straw return could effectively increase soil total nitrogen content and wheat yield. The rotational tillage in wheat and no-tillage in rice was suitable for this area and could also be combined in different years to promote the application of rotational tillage in wheat production.