A solution-dyed protein fiber of the present invention includes 0-100 mass% of silk fibroin and 100-0 mass% of a polypeptide derived from spider silk proteins when the protein fiber is assumed to be 100 mass%, wherein the solution-dyed protein fiber contains a solution-dyeing colorant. The fiber is obtained by: dissolving or dispersing a solution-dyeing colorant in a solvent used for a spinning solution or in dimethyl sulfoxide, thereby preparing a coloring liquid; adding a solvent to the coloring liquid in an amount necessary for a spinning solution; adding and dissolving protein powder into the solvent, thereby preparing a spinning solution; and subjecting the spinning solution to wet spinning or dry-wet spinning. Thereby, the present invention provides a low-cost solution-dyed protein fiber in which a solution-dyeing colorant is dispersed uniformly and that can exhibit bright color tone, and a method for producing the same.