Ecological benefit has been largely applied in China since the 1980s. However, in the 1990s, the concept of ecological benefit was overshadowed by the introduction of the concept of ecosystem service. This paper explores the definition of the ecological benefit, as well as its relationship to ecosystem service, its formation mechanism, and the main features, thereby providing theoretical consideration for the incorporation of ecological benefit into evaluation index system for social and economic development in China. Here, the ecological benefit is defined as the improvement of the conditions for human survival and socio-economic progress derived from ecosystems and their changes. It stresses that the mechanisms for the formation of ecological benefits include: ecosystem functioning mechanism, ecosystem internal stability mechanism and human-natural coupling mechanism. Nine characteristics of ecological benefit include ecosystem mediation, human well-being, regional context dependence, sustainable regeneration, multidimensionality, multiple scale, externality, fundamentality, and non-marketability. This offers a scientific basis for establishing a methodology for ecological benefit monitoring and evaluation and for comparing the results of different studies.