<p>Nowadays, alternative and more sustainable methods and materials, such as biopolymers, are being employed to reduce the environmental effects of these processes. Persian gum, derived from wild almond trees, emerges as a new source of carbohydrate polymers and, due to its unique properties, serves as a sustainable and low-cost additive for improving soil properties. However, studying its behavior in soil environments requires further research. This study examines the application of Persian gum in the stabilization process of silty sand soil and compares it with Xanthan gum. For this purpose, a series of micro and macro-scale tests, including standard Proctor compaction, unconfined compressive strength (UCS), indirect tensile strength (ITS), ultrasonic pulse velocity (UPV), direct shear tests, and scanning electron microscopy (SEM), were conducted on soil stabilized with various contents of Persian gum and Xanthan gum to investigate short-term and long-term behavior. The results indicated that adding carbohydrate polymers led to a decrease in maximum dry density (MDD) and an increase in optimum moisture content (OMC). Adding anionic biopolymers increased the UCS and ITS of the silty sand soil. Additionally, carbohydrate polymers enhanced cohesion while reducing the internal friction angle of the silty sand. The results demonstrated the effective performance of Persian gum compared to common hydrocolloids, such as xanthan gum, in binding soil particles, filling voids, and forming larger aggregates. The UPV test proved a non-destructive and efficient method for evaluating biopolymer-stabilized soils' mechanical and shear parameters, including those stabilized with Persian gum. In addition, the investigation of the microstructure of the stabilized soils showed that the addition of Xanthan gum and Persian gum led to the formation of bonds between the particles of the stabilized soil. Also, the microstructure of the soil stabilized with Xanthan was denser than that of the soil stabilized with Persian gum.</p>