Due to the technological importance that the extrusion process represents in the application of fast food, the objective of this work was to apply pregelatinized rice and sorghum flours in the development of an instant preparation soup and to evaluate its centesimal, technological, and their sensorial analysis. Ten formulations of the instant soup were prepared from the mixtures experimental design. According to the experimental results, it can be stated that the predicted values corroborated with the experimental values, that is, a mixture was obtained for the instant soup with the characteristics of water absorption, water solubility, color, luminosity and viscosity close to the predicted by the models. After the physical and chemical analysis, the microbiological characterization of the best formulation defined by the desirability test was used, which demonstrated that the product is suitable to microbiological standards. The results obtained showed that the 80:10:10 instant soup formulation of pregelatinized rice flour, pregelatinized sorghum flour and potato starch allowed the experimental development of a new product with good nutritional characteristics benefits. It was obtained a food with good technological characteristics solubility and absorption in water, good viscosity, light color and with good sensory acceptance by the tasters.