Water cycle on Mars is one of the big issues because recently it is suggested that a large amount of ice exists under the soil. We investigate the map of isotopic ratio in water vapor by Subaru telescope and compare with the GCM model for understanding of water cycle on Mars. Also, we attempt to derive vertical profile of the water vapor. Very recent study shows super saturation of water vapor and it needs further research of its vertical profile. In future, we plan to do continuous observation of the trace gases with our developing infrared heterodyne spectrometer at our Hawaii Haleakala telescope.