The composition is a significant issue for corrosion resistance of metallic materials. To reveal the correlation of corrosion behavior between multiprinciple alloys and their constituents, a series of single-phase equiatomic alloys of CoCrNi, CoCrNiFe and CoCrNiFeMn was fabricated. The electrochemical and scanning electron microscope results demonstrated that corrosion resistance of the equiatomic alloys in 0.1 M NaCl solution is located in the range but not the average value of their constituents. X-ray photoelectron spectroscopy analysis indicated that the protective performance of passive film is mainly determined by the constituent with the highest corrosion resistance and the breakdown of passive film is mainly dominated by the elements with the highest corrosion rate. Our findings can guide the materials design of multiprinciple alloys with expected corrosion performance.