Numerous studies have demonstrated that a lot of microorganisms, named mycorrhization helper bacteria, play an important role in driving mycorrhizal formation and function. Ectomycorrhizae is a key factor in forest ecosystem. Some ectomycorrhizal macrofungi are abundant and with medicinal and economic value. In this review, we summarized the effects of promoting microorganisms associated with ectomycorrhizal fungi on its functions and the underlying mechanisms for promoting mycorrhization, growth of fungal hyphae, and formation of fruitbody. We also explored the colonization mechanism of promoting microorganisms and its contextdependence as well as ecological function. Meanwhile, we reviewed the interaction between ectomycorrhizal fungi and these microorganisms. Then, we outlined the prospects of promoting microorganisms forfurther research and presented some new ideas for the research on growth, development, and ecological function of ectomycorrhizal fungi.