The electrospinning technique can be used to produce nanometric fibers with high surface area. The nanofibers are suitable for a wide variety of applications, such as bioactive encapsulation, pharmaceutical area and tissue engineering. The objective of this work was to produce biodegradable nanofibers by electrospinning technique. The nanofibers were produced from a blend of 10% soy protein isolated (SPI) in acetic acid, and 30% zein and 3% polyethylene oxide (PEO) both solubilized in 70% ethanol. The polimeric solutions were evaluated by apparent viscosity and electrical conductivity. The nanofibers were evaluated by the morphology and average diameter using scanning electron microscopy (SEM) and thermal stability by thermogravimetric analysis (TGA). The pure polymers were analyzed separately by TGA in order to evaluate the nanofibers thermal stability. The combined polymeric solution presented apparent viscosity and electrical conductivity values similar to the pure zein solution. This can be attributed to a higher mass concentration in relation to the other solutions, since both viscosity and conductivity are affected by the presence of macromolecular solutes in the solution. The nanofibers showed uniform and smooth surfaces and a cylindrical shape, with an average diameter of approximately 270 nm. The mass losses for SPI, PEO and zein were 42.9%, 111.8% and 84.1%, respectively. The nanofibers presented mass loss of 81.1%, and the zein was the constituent that most influenced its thermal stability. It was possible to obtain nanofibers from biodegradable and biocompatible polymers with potential application for encapsulation of bioactive compounds and use in foods or food packaging.