— This paper presents an eigenvector algorithm (EVA) derived from a criterion using reference signals, in which the EVA is applied to the blind source separation (BSS) of instantaneous mixtures. The proposed EVA works such that source signals are simultaneously separated from their mixtures. This is a new result, which has not been clarified by the conventional researches. Moreover, by modifying the criterion, the corresponding EVA which is robust to Gaussian noise is derived. Simulation results show the validity of the proposed EVAs.