The ability to modify food and increase the shelf life by enhanced stability using nonthermal process is of interest to many food companies. Here, we investigate the effects of high hydrostatic pressure (HHP), as a nonthermal process, at various pressure levels (200, 400, and 600 MPa for 30 min) on the functional properties of aqueous dispersions of Alyssum homolocarpum seed gum (AHSG). In this regard, the rheological properties, foam stability, and emulsion stability of the HHP‐treated gums were analyzed and compared. Dynamic oscillatory test indicated that the HHP‐treated gums had more gel‐like behavior than viscous‐like behavior (storage modulus > loss modulus) at designated pressures. When AHSG was treated by HHP, both elastic (G′) and viscous (G″) moduli were increased compared to the native AHSG. The native‐ and HHP‐treated gums exhibited a shear‐thinning (pseudoplastic) behavior. Furthermore, the pressure levels have a significant effect on consistency coefficient, flow behavior index, and yield stress (p < .05) of AHSG. The results showed that the HHP‐treated gums lead to improve the foam and emulsion stability of AHSG. Finally, we assume that HHP‐treated AHSG improves texture in the food materials.