Abstract: At present, rotary tillage is a conventional farming method in wheat-maize rotation system in North China Plain, however, under the rotary tillage year after year, plough pan tends to become shallow and harden, which results in poor ventilation and drainage, and also is hard to increase grain production, especially in the farmland of lime concretion black soil. Using 'Zhoumai27' as the test material, the field experiment was conducted to research the effects of 3 tillage practices (no tillage, rotary tillage and deep tillage) on grain yield of winter wheat, soil bulk density, soil organic carbon and soil inorganic nitrogen, in order to select the appropriate tillage practices and further improve the potential of grain production in the farmland of lime concretion black soil. The results showed: 1) In terms of soil bulk density, there were no significant differences among 3 tillage treatments in 0-10 cm soil layer during wheat growth period, and also no differences at maturity period of wheat in >30-40 cm soil layer, but deep tillage practice could significantly decrease (P<0.05) soil bulk density in >10-30 cm soil layer compared with no tillage. 2) There were no significant differences among 3 tillage practices in 0-20 cm soil layer, but deep tillage could increase (P<0.05) the content of soil organic carbon in >20-40 cm soil layer compared with no tillage. 3) In 0-20 cm soil layer, compared with no tillage or deep tillage, rotary tillage significantly increased (P<0.05) the contents of nitrate nitrogen in the seedling, wintering and anthesis period of winter wheat. However, the content of nitrate nitrogen at jointing stage did not reach significant difference among 3 treatments, and was significantly higher (P<0.05) under no tillage than under rotary tillage and deep tillage at maturity of wheat. In >20-40 cm soil layer, the higher content of nitrate nitrogen was detected in rotary tillage in seedling and anthesis period, and no tillage was higher at other growth stages of winter wheat. 4) In terms of the content of ammonium nitrogen in soil, in 0-20 cm soil layer, during the seedling, wintering and anthesis period of winter wheat there were no significant differences between rotary tillage and deep tillage, but no tillage showed higher values. At jointing stage, the order of the content of ammonium nitrogen was rotary tillage > deep tillage > no tillage, and also there was significant differences among 3 tillage treatments (P<0.05), but at maturity stage, the content of ammonium nitrogen in 3 treatments did not reach significant differences. In >20-40 cm soil layer, the order of the content of ammonium nitrogen was deep tillage > rotary tillage > no tillage during the whole growth period of winter wheat. 5) Compared with no tillage, deep tillage could significantly increase (P<0.05) grain yield of winter wheat mainly, for deep tillage increased 1000-grain weight and grain number. To sum up, under the condition of our field experiment, deep tillage could decrease soil bulk density in >10-30 cm soil layer, improve the content of organic carbon and ammonium nitrogen in >20-40 cm soil layers, and also increase grain yield of winter wheat in the end. Therefore, deep tillage practice should be selected as an appropriate tillage practice in the farmland of lime concretion black soil.