Abstract: The present disclosure provides an adsorption tower for an oxygen generator system configured to adsorb nitrogen in air and supply oxygen, the tower comprising: a housing defining an inner space therein in which an adsorbing agent is filled; a housing inlet through which air enters into the housing; an housing outlet through which air is discharged from the housing, wherein the housing inlet is opposite to the housing outlet; a sodium based adsorbing agent layer disposed in the inner space and adjacent to the housing inlet; and a lithium-based adsorbing agent layer disposed in the inner space and adjacent the housing outlet.