Abstract: This paper discusses the origins, contents and definitions of landslip, landslip group and landslip zone. And then we create a new word: population landslide. The correlation, classification and group pattern have also been simply defined. This paper enumerates a large number of examples from the North and South of China, and introduces the developing characteristics and plane component features of five basic combination patterns. This population landslide research broadens the field of geological disaster, enriches the existing theory, and provides a large-scale risk assessment and prevention. At last the paper point out that to study the landslide group, the researcher must make clear the combination type, and then the law of the new landslide will be made known.