Abstract: This paper outlined the "Threc, North" protection forest system, discribed the guiding ecology and economical line in establishment of shelter forest system, and further discussed the significance and foundation of renewing the concept of "froestry". The academic concept of ecology-economical type of shelter forest system (ESSFS) and its relation with the formation of regional artificial ecosystem are introduced. Taking a demonstration area of ESSFSin Xinshuihe basin on loess plateau as an example, the paper discussed the technical connotation, composition and ecology-eco nomical characteristics of ESSFSin hilly mountain areas. The author summarized some points of enlightenment from the practice of shelter forest project on the better establishment of shelter forest engineering in other regions.

Key words: Shelter forest system, Ecology-economical type, Artificial ecosystem