Nanofibers produced from plant- and animal-derived proteins using the solution-blowing method were collected and their mechanical properties were characterized and compared with those of synthetic polymer samples that were produced and collected similarly. Soy protein, zein, lignin, and cellulose acetate were the plant-derived proteins and silk protein (sericin) and bovine serum albumin were the animal-derived proteins used in the present work to form nanofibers by solution blowing. The aim of this work is to demonstrate that solution blowing can be successfully used to form nanotextured nonwovens from a number of biopolymers, which is of significant interest for a wide range of applications such as filtration, packaging, bioplastics and biomedical materials. Tensile tests were used to elucidate mechanical properties of such nanofiber mats. It was also shown that hot and cold drawing can be applied as a post-treatment to further enhance their mechanical performance.