The invention discloses a manufacturing method for a prefabricated part of a propeller blade.The method includes the steps that a knitted mandrel is designed according to a product digital mold, the mandrel is partitioned according to the features of the blade, technological parameters of the ratios of spindle rotating speeds of all regions to the axial movement speed of the mandrel and the number of weaving layers are pre-designed, and then the prefabricated part is knitted.The method is high in automation degree and suitable for batch production.The obtained prefabricated part is good in forming, stable in quality, good in repeatability and suitable for engineering application, and the problems that a prefabricated part, with the high variability of the shape, dimension and structure, of a propeller blade cannot be directly formed through two-dimensional knitting, and knitting is conducted in the production process through an artificial trail and error method are solved.