The development of stream ecology, especially the progress of that field in North America, has been briefly reviewed, and stream studies in Korea were analyzed through literature survey. During the last two decades, theoretical advances in stream ecology and understanding of the structure and function of stream ecosystem were made from the studies mainly in North America. Early studies (1960-1970) focused on determination of the environmental factors controlling the distribution and abundance of organisms dwelling in streams. Introduction of conceptual development, such as the functional feeding concept, river continuum concept, and nutrient spiraling was notable in the late 70's and the 80's. For last 20 years, experimentation approaches to apply ecological principles were very fruitful in the understanding of community structure. Even though studies on the stream ecosystem is Korea have a long history, most of works were concentrated on limited subjects: water quality, abundance and distribution of aquatic insects and fishes. Basic ecological attributes of stream organi는 and test of ecological principles have rarely been a subject of research topics. We must concentrate our effort to enhance our understanding of stream and river ecosystem through qualitative, experimental and interdisciplinary approaches.