To provide an ink stock solution excellent in handleability, a method for producing the same, an ink composition using the ink stock solution, particularly suitable for an ink for inkjet recording, and a method for producing the same, the ink stock solution includes a dye and a viscosity reducing agent, wherein the ink stock solution has a solid concentration of the dye of 7% or more by weight; the method for producing the ink stock solution includes adding a dye to a water and dissolving the dye in the water, and then, adding a viscosity reducing agent to control the viscosity; the method for producing the ink stock solution includes dissolving a dye, a water and a viscosity reducing agent all together; and the ink composition includes the ink stock solution and has a viscosity of 1 to 30 mPas.