The purpose of this study was to investigate the effects of sonication time and temperature on physical properties of native and cross-linked wheat starches. Starch aqueous dispersions (30%, w/w) were sonicated with an ultrasonic probe at 20kHz, 100% wave amplitude and sonication power of 100W for 5, 10, 15 and 20min at 5 and 22C. Increase in cold-water solubility, decrease in intrinsic viscosity, gelatinization enthalpy, peak, trough, setback and final viscosities of both starches were observed by increasing the sonication time and temperature. Ultrasonic treatment resulted in the formation of some fissures and cracks on the exterior of the granules as observed by a scanning electron microscope. In general, the effects of ultrasonic treatment on both starches increased with increment in processing time and temperature. The cross-linked wheat starch was more resistant against ultrasonic treatment than the native counterpart.