Solution blowing of soy protein (sp)/polymer blends was used to form monolithic nanofibers. The monolithic fibers were blown from blends of soy protein and nylon-6 in formic acid. The sp/nylon-6 ratio achieved in dry monolithic nanofibers formed using solution blowing of the blend was equal to 40/60. In addition, solution blowing of core-shell nanofibers was realized with soy protein being in the core and the supporting polymer in the shell. The shells were formed from nylon-6. The sp/nylon-6 ratio;achieved in dry core-shell fibers was 32/68. The nanofibers developed in the present work contain significant amounts Of soy protein and hold great potential in various applications of nonwovens.