Simultaneous-color Wide-field Infrared Multi-object Spectrograph, SWIMS, is one of the first generation instruments for University of Tokyo Atacama Observatory 6.5m Telescope now being constructed at the summit of Co. Chajnantor in northern Chile. SWIMS has a field of view of 9.6 arcmin in diameter, and a dichroic mirror is inserted in the collimated beam to split it into two arms, one covering 0.9-1.45 micron and the other 1.45-2.5 micron. It is capable of two-color simultaneous imaging or R~1000 multi-object spectroscopy at 0.9-2.5 micron wavelength range with a single exposure, and enables us to carry out efficient NIR imaging/spectroscopic surveys.SWIMS is expected to be transported to the Subaru telescope in FY 2016 and planned to be install on the Cassegrain focus of the telescope to carry out first-light and engineering observations.In this presentation, we will introduce the specifications and current status of SWIMS, and wide-field imaging surveys utilizing medium-band filters being proposed.