Taking two crops, summer corn and winter wheat, as an integrated system, the conservation tillage system is studied for two crops a year region in North China Plain. Two experimental factors are chosen, one is tillage method, which includes no-tillage, subsoiling, harrowing and moldboard plowing, and the other is crop residue cover rate which consists of 100%, 50% and 0. Eight kinds of conservation tillage systems and two kinds of conventional plough systems are designed. Soil parameters including moisture content, soil bulk density, soil temperature and crop indexes including density of roots, crop yield are measured during the study period. The experimental result shows that application of conservation tillage in North China Plain is benefit to saving water, enhancing water use efficiency and increase crop yield. The two suitable systems of conservation tillage are obtained, they are corn-wheat no-tillage and 100% cover, subsoiling for corn with no-tillage for wheat and both 100% cover.