In an adsorbing body for humidity and odorous gas exchange such as an adsorbing sheet for dehumidification, an adsorbing element for dehumidification or an adsorbing element for total heat energy exchange, a sheet or a honeycomb laminate is impregnated or coated with silica sol containing, as solid content, not more than 30% of the silica sol weight of minute silica particles not larger than 120 .ANG. in diameter which contain many stable silanol radicals on the surface and 0.01-1% of alkali metal ion Na.sub.2 O. It is then dried to rigidly fix silica gel. Other humidity adsorbing or absorbing agents such as zeolite, organic high-polymer electrolyte, etc. may be mixed in said silica sol. Silica gel with excellent humidity adsorbing ability can be strongly adhered to a sheet or a honeycomb laminate in an extremely simple method.