Ground improvement is crucial for the design of structures built on weak soil, both currently and in the future. Chemical stabilization is increasingly favored in ground improvement practice. However, existing literature has focused on studying soil stabilized with conventional materials such as cement and lime, rather than exploring the potential of environmentally suitable chemical stabilizers. Furthermore, a comprehensive assessment of the impact of wetting–drying cycles and curing times has been limited in previous research. This study aims to address these gaps by investigating the mechanical behavior of sand treated with sodium silicate under saturated conditions, both before and after undergoing wetting–drying cycles. Direct shear tests were conducted to comprehensively analyze the shear performance of the sodium silicate-treated sand. The findings revealed that the critical content of sodium silicate for enhancing sand shear strength under saturated conditions is 3%, and that shear strength increases with longer curing times but decreases due to the impacts of wetting–drying (W–D) cycles.