Abstract: The experiment was done from 2011 to 2012 in Tong Liao Academy of Agricultural Sciences. The test maize varieties were Zhengdan958 and Tongke1 and subsoiling treatment was done at maize jointing stage. Three kinds of deep loosening depth were designed： not subsoiling（CK）, subsoiling 30cm（SS30） and subsoiling 40cm（SS40）. Subsoiling makes maize kernel weight, kernel number, seed ratio, ear length and ear diameter increased and makes bare top, pour the discount rate and grain moisture decreased, therefore maize production increased significantly. In 2011, the Zhengdan958 of SS30 and SS40 increased production than contrast and Tongke1 yield increasing rate were 8.11% and 6.92% and subsoiling 40cm（SS40） differences were highly significant（P0.01） and subsoiling 30cm（SS30） differences were significant level（P〈0.05）. In2012, the Zhengdan958 of SS30 and SS40 yield increase rate were 14.58% and 12.87% than contrast and Tongke1 yield increase rate were 13.36%和 11.07% and the differences were highly significant（P〈0.01）.