Abstract: Aiming at the engineering applicability of red mud-based foam light soil, this study carried out a study on the control method of rheological properties of red mud-based foam light soil, and revealed the effect of water/binder ratio and water reducer on rheological properties and compressive strength of red mud-based foam light soil. The experimental results show that, with the increase of water/binder ratio, the rheological properties of the slurry are improved, and the compressive strength first increases and then decreases. After adding polycarboxylic acid water-reducing agent and naphthalene water-reducing agent, the fluidity of the slurry is enhanced, and the polycarboxylic acid water-reducing agent has a weakening effect on the compressive strength, while naphthalene water-reducing agent can improve the compressive strength. Finally, the optimum design value of water-cement ratio and water-reducing agent is determined.