The advent of far-infrared/submillimeter observational facilities showed that a significant fraction of star formation is placed in heavily dust-attenuated galaxies in the early Universe. Due to the nature of galaxy spectral energy distribution and the effect of K-correction, galaxies selected at submillimeter wavelengths are likely to be vigorous star-forming high-redshift galaxies. Based on their characteristics – gas-rich, large stellar mass, frequent contribution from the active galactic nuclei – they are spotlighted to show the early stage of massive galaxy evolution. In this talk, I will introduce several ongoing submillimeter extragalactic surveys, particularly focusing on the JCMT/SCUBA-2 survey on the North Ecliptic Pole region.