We use the multi-channel analysis of surface waves (MASW) method to analyze synthetic seismic data calculated using models with high shear-wave velocity (Vs) contrast. The MASW dispersion-curve images of the Rayleigh wave are obtained using various sets of source-offset and spread-size configurations from the synthetic seismic data and compared with the theoretically calculated fundamentaland highermode dispersion-curves. Such tests showed that most of the dispersion-curve images are dominated by higher-mode energy at the low frequencies, especially when analyzing data from long receiver offsets and thus significantly divert from numerically expected dispersion-curve trends, which can lead to significant Vs overestimation. Further analysis showed that using data with relatively short spread lengths and source offsets can image the desired fundamental-mode of the Rayleigh wave that matches the numerically expected dispersioncurve pattern. As a result, it was concluded that it might be possible to avoid higher-mode contamination at low frequencies at sites with high (Vs) contrast by appropriate selection of spread size and seismic source offset.