The invention discloses a full-working condition performance prediction method for a compressor, and aims at providing a rapid and accurate full-working condition aerodynamic performance prediction method so as to increase the design and optimization efficiency of the compressor. In the method, a formula is established by taking parameters of a design point as the reference to predict the flow, the efficiency and the overall pressure ratio of an off-design working condition; in a flow prediction method, firstly, the flow of the design point is converted according to an empirical formula to flow corresponding to a peak efficiency point at different rotating speeds, and then, blocking flow and surging flow at respective rotating speeds are calculated; in an efficiency prediction method, firstly, the efficiency of the design point is converted according to the empirical formula to peak efficiency at different rotating speeds, and then, the efficiency at different rotating speeds is calculated according to an elliptic piecewise approximation method; and in a prediction method for the overall pressure ratio, work factors at different rotating speeds and different flow are calculated according to the thought of the equivalent width of an impeller exit, and the work factors are combined with current efficiency to obtain the overall pressure ratio. By applying the full-working condition performance prediction method to design and optimization of the compressor, the design cycle can be remarkably shortened, and the design cost is reduced.