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Femtosecond laser-induced resonance-enhanced multiphoton-ionization photoelectron spectroscopy (REMPI-PS)is faced with two drawbacks of low spectral resolution and poor selective excitation due to the broad spectral bandwidth.We propose a scheme to obtain a high-resolution selective excitation of (2+1) REMPI-PS by com-bining π and cosinusoidal phase modulation.Our theoretical results indicate that the (2+1) REMPI-PS signals related to neighboring excited states can be differentiated from their indistinguishable photoelectron spectra by the π phase modulation,and then their selective excitation can be realized by supplementally adding the cosinusoidal phase modulation.Furthermore,the physical mechanism of the high-resolution selective excitation of (2+1) REMPI-PS is explained by considering the two-photon power spectrum.