The invention discloses a manufacturing method for a carbon fiber composite horizontal rotor fan cover of a centrifuge. The manufacturing method comprises the following steps: 1, using carbon fiber tows as raw materials, and impregnating the carbon fiber tows with resin; manufacturing a core body blank in a horizontal rotor fan cover shape by adopting forming methods such as spinning or die pressing of an aluminum plate, and finishing the core body blank to obtain a core body in the horizontal rotor fan cover shape with a certain boundary dimension; 2, winding the carbon fiber tows impregnatedwith the resin around the periphery of the core body in the horizontal rotor fan cover shape to form a reinforcing layer wrapped around the core body; and 3, heating and curing the core body in the horizontal rotor fan cover shape wrapped with the reinforcing layer in an oven to obtain a core body reinforcing body in the horizontal rotor fan cover shape, and carrying out polishing and paint dipping on the outer contour of the core body reinforcing body in the horizontal rotor fan cover shape to form the carbon fiber composite horizontal rotor fan cover with a three-dimensional structure. Thecarbon fiber composite horizontal rotor fan cover has the advantages of light weight, strong corrosion resistance and high strength.