The effect of phosphorus in some typical wrought superalloys including IN718, GH761 and GH4133 has been studied. Phosphorus was not dissolved in the γ matrix of superalloys and was segregated in the residual liquids seriously during solidification, and the solidification of the alloys added with phosphorus was always finished by the precipitation of a phosphorus bearing phase. Two factors controlling the segregation tendency of a minor element were determined, one is the solubility of the element in the matrix, another is the precipitation temperature of a phase in which the element is absorbed. The detrimental effect of phosphorus on the solidification could be eliminated by a proper homogenization treatment. Phosphorus improved the stress rupture properties of the alloys with a fine grain structure. By combining the grain refinement with phosphorus addition, the properties of GH761 alloy was improved efficiently.