We utilize ab initio molecular dynamics simulation to investigate the melts of three representative high-entropy alloys (HEAs) with the similar origins, including NiCoCrFeMn, NiCoCrFe and NiCoCr. The atomic dynamics of those melts at various temperature are systematically studied. Furthermore, we analyze the electronic and atomic structure of their melts, such as the charge transfer, electronic density of states, pair correlation functions and short-range order. Those results are important especially compared directly with the existing information for the liquids of bulk metallic glasses (BMGs), which are usually formed by the combination of multiple metallic components but remains as amorphous phase; the characteristic structural features within BMGs are the icosahedral short-to-medium range order (dominant five-fold symmetry), without long-range translational structure. This work can facilitate further understanding of the phase transformation of HEAs and shed light to predict various behavior of crystalline phase. This work was supported by DoE-BES-DMSE, under Contract No. DE-AC02-05CH11231.