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The preliminary design of multistage axial compressor requires a vast number of design variables and limitations, the simultaneous investigation of which needs a complicated design program. This study provides a new algorithm by the use of combining multi-variable/multi-objective optimizations, meanline simulator and preliminary design program. On the one hand the two-layer optimization is used to consider all design variables and on the other the design limitations are put into the cost function together with surge margin and efficiency. The comparison of the results with the NASA transonic eight-stage compressor shows the ability of the new algorithm to achieve a compressor with better performance and lower weight.