The invention discloses a high-strength viscose fiber and a production method thereof, which are characterized in that the viscose fiber is formed by mixing bacterial cellulose and viscose spinning solution, wherein the content of the bacterial cellulose in the viscose fiber is 1 to 10 percent. The production method comprises the following steps: the flake bacterial cellulose is pre-processed, and then the flake bacterial cellulose after the preprocessing is smashed with a ball milling method to obtain a micro nano-grade bacterial cellulose powder; the bacterial cellulose powder is added into the viscose spinning solution to be uniformly scattered and defoamed to obtain a spinning solution; and the spinning solution is made into a high-strength viscose fiber. The content of the bacterial cellulose in the viscose fiber is 1 to 10 percent. The viscose fiber which is prepared with the production method has high strength, small shrinkage and good elasticity, can be blended and interwoven with cotton, wool and other synthesized fibers to be used for the fields such as top-grade costume fabric and industrial textiles, and the like.