Method for storing selectively gas by controlling gas storing space of gas storage medium

PURPOSE: A selective gas storage method is provided to selectively store desired gas only by controlling the gap or lattice distance between crystalloids of a gas storage medium. CONSTITUTION: The gap(220) between crystalloids(210) or the lattice distance between the crystalloids is controlled, relative to the van der Waals diameter of gas(230) to be stored, by changing the heat treatment temperature of the gas storage medium or employing a chemical reactor in sample synthesis of the gas storage medium so that the gas is stored selectively.