[Objective] The research on the water - holding characteristics and strength characteristics of unsaturated lime - treated loess cushion aims to reveal the influence laws of different lime contents on its suction and strength, providing guidance and reference for the construction and theoretical research of the foundations and subgrades of loess buildings. [Methods] Indoor soil - water characteristic tests and unsaturated triaxial tests were conducted to study the soil - water characteristics, unsaturated strength and softening constitutive model of lime - stabilized unsaturated loess. Four lime contents were set, namely 0%, 3%, 6% and 9%, aiming to reveal the influence law of lime content on matric suction. When studying the influence of matric suction on strength, the matric suction was set at 0 kPa, 50 kPa, 100 kPa and 200 kPa respectively, so as to explore the influence law of matric suction on its strength. [Results] ① The greater the lime content, the greater the matric suction. ② A soil - water characteristic model considering the influence of lime content is proposed, and this model can accurately describe the soil - water characteristics of lime - stabilized loess. ③ The cohesion and internal friction angle of the stabilized soil increase with the increase of lime content. When the lime content is 9%, as the matric suction increases, the cohesion of the lime - stabilized loess gradually increases, while the change in the internal friction angle is very small. ④ A softening model that can better describe the lime - stabilized loess is obtained. A nonlinear model capable of describing the softening behavior of lime - stabilized loess is established by introducing a damage variable. [Conclusion] The influence of lime content on the soil - water characteristics of stabilized loess cannot be ignored. Meanwhile, the use of a nonlinear model can accurately describe the stress - strain curve of lime - stabilized soil, and the results are relatively good.