In order to study the effect of locust bean gum to improve the strength of clay, unconfined compressive strength tests and tensile tests were conducted on improved clay with different curing ages and locust bean gum contents. The results indicate that the addition of locust bean gum can significantly improve the compressive and tensile properties of clay. When the curing age is fixed, with the increase of the locust bean gum content, the compressive and tensile strengths of the improved clay show an increasing trend. Through comparison, it can be seen that the optimal content of locust bean gum is 2%, and the maximum compressive and tensile strengths of the sample are increased to 425.74 and 234.61 kPa, respectively, which are about 1.8 times higher than those of the plain soil; When the dosage of locust bean gum is constant, the curing age also has a certain impact on the compressive and tensile strengths of the improved clay. Under the same dosage of locust bean gum, when the curing age is 7 days, the specimen compressive and tensile strength enhancement is the largest, the maximum enhancement is 68.12 and 34.39 kPa, respectively. Robinia pseudoacacia bean gum forms a layer of gum film on the surface of soil, and uses its own ductility to fill the pores between soil particles, improving the particle structure of the soil and its stability, and thus the strength characteristics of clay. As the curing age increases, the gum film gradually shrinks, making the arrangement of soil particles more compact, thereby improving the unconfined compressive strength and tensile strength of the improved cohesive soil.