The wettability of colloid particles play a key role in the formation and stability of Pickering emulsions. Gliadin colloid particles (GCPs) possessed strong hydrophilicity at acidic condition (~pH 3.0) due to the high positive charge, thus tended to partition within the continuous phase, resulting in unstable emulsions. In this study, gliadin colloid particles (GCPs) was used as an effective particulate stabilizer to prepare stable oil-in-water Pickering emulsions via ultrasonic approach. Oil leaking occurred for the control Pickering emulsions produced by shearing after three days of storage, while the sonication treatment significantly enhanced its stability especially when ultrasonic power high than 40%. Viscoelastic and gel-like Pickering emulsion with good stability for more than five months were successfully prepared in our work. The mean droplet size was < 5 μm for the emulsions fresh and after 2 months of storage. The interfacial structure of emulsion, the partition of gliadin colloid particles and the aggregation behavior of the droplets were investigated to relate them with the stability of the emulsions, and the stability mechanism of the related Pickering emulsions was clarified. The food-grade surfactant-free Pickering emulsion stablized by GCPs shows promising application prospects in the nutrients delivery.