AbstractMoso‐bamboo (Phyllostachys edulis), with the favor of human disturbance, rapidly invades adjacent forests to form monocultures in East Asia. Moso‐bamboo not only intrudes the broadleaf forests but also the coniferous, and it could impact by above‐ and below‐ground pathways. However, it still remains unclear whether the below‐ground performance of moso‐bamboo differs from broadleaf to coniferous forests, especially those differing in competitive and nutrient acquisition strategies. In this study, we investigated three types of forest stands in Guangdong, China, including a bamboo monoculture, a coniferous forest, and a broadleaf forest. We found that moso‐bamboo may suffer stronger soil P limitation (soil N/P = 18.16) and may be infected by more AMF in coniferous than broadleaf forests (soil N/P = 16.17). Based on our PLS‐path model analysis, soil P resource may be the key to differ moso‐bamboo root morphology and rhizosphere microbe in different forests: in broadleaf forests with weaker soil P limitation, may be realized through increasing specific root length and specific surface area, whereas in coniferous forests with stronger soil, P limitation may be realized through combining more AMF. Our study highlights the importance of underground mechanisms about moso‐bamboo expansion in different forest communities.