A method for manufacturing a composite fiber component for a rotor blade of a wind turbine that includes introducing a fiber material into a mold, supplying a flowable matrix material via a longitudinally extending runner of the mold using a vacuum infusion method such that the fiber material is soaked with matrix material from the runner and the matrix material flows transversely to the longitudinal extension of the runner such that a first region of the fiber material is substantially soaked with matrix material from a first section of the runner and a second region of the fiber material is substantially soaked with matrix material from a second region of the runner, and matrix material flow rates are set for the first section and the second section of the runner depending on thicknesses of the fiber material in the first region and the second region of the runner, respectively.