In a range of a wind velocity of 0.5 to 3.5 (m/s) in a refrigeration cycle, when combining absorbent having a small dependency on the wind velocity and the refrigeration cycle, it is not possible to vary dehumidification capability by changing the wind velocity and matching with an actual load is poor. In a refrigerating and air conditioning apparatus having a refrigerator 20 in which refrigerant is put, and having a compressor 20a for compressing the refrigerant, a condenser 20b, and a throttle device 20c, and an evaporator 20d, and a desiccant rotor 1, which is water adsorption means, an adsorbent is supported with the desiccant rotor 1, whose time constant at a water adsorption equilibrium becomes small as a wind velocity increases in the range of the wind velocity of 0.5 to 3.5 m/s, the condenser 20b is disposed upwind of the desiccant rotor 1, and the evaporator 20d is disposed downwind of the desiccant rotor 1.