Disclosed is a benzimidazole-based injection solution which does not cause hemolysis or local irritation when used as an injection solution. Specifically disclosed is a method for producing a benzimidazole-based injection solution, which comprises a step of preparing a benzimidazole-based solution by mixing a benzimidazole-based compound or a salt thereof and ammonia water in an aqueous solvent that contains no nonaqueous solvent, and a step of freeze-drying the solution. By this method, a benzimidazole-based injection solution which does not cause hemolysis or local irritation when used as an injection solution can be obtained. Since a benzimidazole-based compound or a salt thereof is sufficiently dissolved in an aqueous solvent that contains no nonaqueous solvent and is highly stable in the solvent, a high-quality benzimidazole-based injection solution can be obtained. In addition, the benzimidazole-based injection solution obtained by the method has excellent storage stability.
