Utilizing a global database detailing the impact of drought on plant biomass allocation, this study focused on the three most prevalent types: arbuscular mycorrhiza(AM), ectomycorrhiza(ECM) and amphigenetic mycorrhiza (AM+ECM). The goal was to explore alterations in organ-specific biomass allocation in these mycorrhizal plants in response to drought. Employing a general linear model, the relative growth rate among organs was simulated and analyzed, shedding light on how different mycorrhizal plants adjust their biomass allocation in reaction to drought. The results revealed that under drought conditions, the allocation of root biomass(MR) increased by 8.2% for AM plants and 7.6% for AM+ECM plants, while ECM plants exhibited no significant change in the allocation of MR. The allocation of stem biomass(MS) decreased by 7.7% for AM plants under drought condition, but remained constant for ECM and AM+ECM plants. The allocation of leaf biomass(ML) experienced a decrease of 9.4% for AM+ECM plants and 6.5% for ECM plants under drought, while ML of AM plants remained relatively stable. When subjected to drought, the biomass accumulation rates of roots, stems and leaves followed a decreasing pattern for AM and AM+ECM plants. Conversely, ECM plants witnessed a decreasing accumulation pattern for stems, leaves and roots. The strategies employed by different mycorrhizal plants in response to drought diverge: AM plants increased roots biomass by decreasing the biomass allocation of stems and reproductive organs, AM+ECM plants prioritized augmenting root biomass through diminished leaf biomass allocation, and ECM plants solely decreased the biomass of leaves with minimal changes in the biomass of roots and stems. Consequently, mycorrhiza emerges as a pivotal factor when contemplating plant response strategies to drought.