With the relationships between species diversity and ecosystem function being one of focuses in the field of ecology, removal experiment of species or function groups has been applied broadly. Its applications in ecology include the studies on: (1) interspecific relationships; (2) the relationships between species diversity and ecosystem functioning; (3) the functions of key species; and (4) the assessment of the consequences of invasive species to the ecosystem. According to the features of removal experiment, some issues deserving attention were put forward, including the effects of the removal action itself on the ecosystem of temporal scales on the research results in removal experiment, and the specialty of removal of invasive species.