Due to its ready-to-eat characteristic, instant flour is widely preferred by consumers and has great marketing potential. This study examines the influence of cold and hot slurry feed on physicochemical and ready-to-eat properties of the wheat flour pregelatinized by drum-drying. Results are as following: The pregelatinized hot slurry of wheat flour, because of its long heating time, became slightly yellow. Different kinds of viscosities such as peak viscosity, final viscosity, break viscosity and setback viscosity were also compared, and the results showed that the cold slurry had higher value than hot slurry feed. Cold slurry had a smaller particle size and greater swelling power, but the WSI and separation ratio are lower than hot slurry. The drum-dried pregelatinization of the two samples, cold and hot slurry, could be grounded into powder, their polarized light photomicrographs and X-ray diffraction peak were not detected, showed that gelatinization had reached to 100%. The hot slurry can get a better separation ratio when pregelatinized for 5 minutes at 85℃.